Includes fix for Bug #38180, "options are read from ~/my.cnf instead of ~/.my.cnf"

Includes fix for Bug #38180, "options are read from ~/my.cnf instead of ~/.my.cnf"

Pull out some of unpack_dirname() into normalize_dirname(); this
new function does not expand "~" to the home directory.  Use this
function in unpack_dirname(), and use it during init_default_directories()
to remove duplicate entries without losing track of which directory
is a user's home dir.

libmysqld/emb_qcache.cc:
  Fixed build warning on Windows:
  ported the fix from 6.0 in 5.1

offset for time part in UUIDs was 1/1000 of what it
should be. In other words, offset was off.

Also handle the case where we count into the future
when several UUIDs are generated in one "tick", and
then the next call is late enough for us to unwind
some but not all of those borrowed ticks.

Lastly, handle the case where we keep borrowing and
borrowing until the tick-counter overflows by also
changing into a new "numberspace" by creating a new
random suffix.

mysql-test/r/func_misc.result:
  Show that time-part of UUIDs is correct now.
mysql-test/t/func_misc.test:
  Show that time-part of UUIDs is correct now
  by replicating the C-code's resultin SQL.
  Results also decode to expect date-data on
  command-line (external validation).
  
  No test for unwinding of borrowed ticks as
  this a) is a race and b) depends on what timer
  we get.
sql/item_strfunc.cc:
  correct offset for date/time-part of UUID.
  also make sure that when we counted into
  the future earlier (several UUIDs generated
  in same tick), we only give back as many
  "borrowed" ticks as we can without duplicating
  past timestamps. If our tick-counter overflows
  before we can give back, or if the system-clock
  is set back (by user or Daylight Saving Time),
  we create a new random suffix to avoid
  collisions and clear the tick-counter.

offset for time part in UUIDs was 1/1000 of what it
should be. In other words, offset was off.

Also handle the case where we count into the future
when several UUIDs are generated in one "tick", and
then the next call is late enough for us to unwind
some but not all of those borrowed ticks.

Lastly, handle the case where we keep borrowing and
borrowing until the tick-counter overflows by also
changing into a new "numberspace" by creating a new
random suffix.


mysql-test/r/func_misc.result:
  Show that time-part of UUIDs is correct now.
mysql-test/t/func_misc.test:
  Show that time-part of UUIDs is correct now
  by replicating the C-code's resultin SQL.
  Results also decode to expect date-data on
  command-line (external validation).
  
  No test for unwinding of borrowed ticks as
  this a) is a race and b) depends on what timer
  we get.
sql/item_strfunc.cc:
  correct offset for date/time-part of UUID.
  also make sure that when we counted into
  the future earlier (several UUIDs generated
  in same tick), we only give back as many
  "borrowed" ticks as we can without duplicating
  past timestamps. If our tick-counter overflows
  before we can give back, or if the system-clock
  is set back (by user or Daylight Saving Time),
  we create a new random suffix to avoid
  collisions and clear the tick-counter.

   "funcs_2: The tests do not check if optional character
               sets exist."
2. Minor cleanup

The problem is that relying on the output of the 'ls' command is not
portable as its behavior is not the same between systems and it might
even not be available at all in (Windows).

So I added list_files that relies on the portable mysys library instead.
(and also list_files_write_file and list_files_append_file,
since the test was using '--exec ls' in that way.)

client/mysqltest.c:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  To be able to replace the use of '--exec ls' I have added
  list_files, list_files_write_file and list_files_append_file.
  
  list_files <dirname> [<filename incl. wild-cards>]
  is equivalent to 'ls <dirname>/[<filename incl. wild-cards>]'
  
  list_files_write_file creates/overwrites a file with the content
  list_files_append_file creates/appends a file with the content
  list_files* return a sorted output.
mysql-test/r/mysqltest.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  result file change, due to added test of the new list_files command.
mysql-test/suite/parts/inc/partition_check_drop.inc:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Using the new list_files instead of 'ls'.
  
  Changed the use of local variables (ls_file, file_list)
  and server variable (@aux).
mysql-test/suite/parts/inc/partition_layout.inc:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Using the new list_files instead of 'ls'.
mysql-test/suite/parts/inc/partition_layout_check1.inc:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Using the new list_files instead of 'ls'.
mysql-test/suite/parts/inc/partition_layout_check2.inc:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_alter1_1_2_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_alter1_1_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_alter1_2_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_alter2_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_alter3_innodb.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_alter3_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_basic_innodb.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_basic_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_basic_symlink_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_engine_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/suite/parts/r/partition_syntax_myisam.result:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Replaces '--exec ls' with list_files.
  Removal of the directory part of file listing.
mysql-test/t/mysqltest.test:
  Bug#35736 Test 'parts.partition_basic_symlink_myisam' depends on output of 'ls'
  
  Adding test for the new mysqltest commands list_files,
  list_files_write_file and list_files_append_file.

Fixed the test to expect the correct result.
The previous test script was in fact affected by 26030,
and wrongly expected a ER_PARSE_ERROR error.

problem was that ha_partition::records was not implemented, thus
using the default handler::records, which is not correct if the engine
does not support HA_STATS_RECORDS_IS_EXACT.
Solution was to implement ha_partition::records as a wrapper around
the underlying partitions records.

The rows column in explain partitions will now include the total
number of records in the partitioned table.

(recommit after removing out-commented code)