Simple optimzations and cleanups
Removed compiler warnings and fixed portability issues
Added client functions 'mysql_embedded()' to allow client to check if we are using embedded server
Fixes for purify


client/mysqlimport.c:
  Remove not used variable
client/mysqltest.c:
  Remove usage of MAXPATHLEN (all MySQL code uses FN_REFLEN)
  Simplified code
  Remove usage of sprintf("%llu") as this is not portable
include/mysql.h:
  Added mysql_embedded() to be able to easily check if we are using the embedded server
innobase/srv/srv0start.c:
  Don't use memcmp() when using purify (to avoid false warnings)
libmysql/libmysql.c:
  Added mysql_embedded() to be able to easily check if we are using the embedded server
libmysql/libmysql.def:
  Added mysql_embedded() to be able to easily check if we are using the embedded server
myisam/myisam_ftdump.c:
  Remove compiler warning
myisam/myisamchk.c:
  Remove compiler warning
myisam/rt_test.c:
  #ifdef not used code
mysys/hash.c:
  Remove compiler warning (from last push)
mysys/my_gethwaddr.c:
  Remove compiler warning
ndb/src/ndbapi/ndberror.c:
  #ifdef not used code
regex/regcomp.c:
  Remove not used code
regex/regcomp.ih:
  Remove not used code (to remove compiler warnings)
sql-common/client.c:
  Remove compiler warnings
sql/field.cc:
  Simple optimization
sql/ha_innodb.cc:
  Rename mysql_embedded -> mysqld_embedded
sql/item.cc:
  Fix comments
  Move variables first on block
  Remove else after return
  Simple optimizations
  (no logic changes)
sql/item_cmpfunc.cc:
  Added comment
sql/mysql_priv.h:
  Rename mysql_embedded -> mysqld_embedded
sql/mysqld.cc:
  Rename mysql_embedded -> mysqld_embedded
sql/sql_acl.cc:
  Added comments
  simple optimization
  Fixed 'very unlikely' bug when doing REVOKE ALL PRIVILEGES
sql/sql_select.cc:
  More comments
  Simple optimization
sql/sql_show.cc:
  Simple changes to make similar code similar
  More comments
sql/sql_string.cc:
  Trivial optimization and better code layout
strings/Makefile.am:
  Change xml.c to use bcmp to avoid warnings from purify
strings/xml.c:
  Change xml.c to use bcmp to avoid warnings from purify
tests/client_test.c:
  Remove usage of MAXPATHLEN (all MySQL code uses FN_REFLEN)