encrypted tables

Introduced a new innodb_default_page_encryption_key configuration
variable to allow user to set the default key identifier.

put cracklib_password_check into a separate package.
build it conditionally on Debian/Ubuntu

namely, remove the code to support:
etch, lenny, hardy, intrepid, jaunty, karmic, maverick, natty

Remove ONLY_IF clause in MYSQL_ADD_PLUGIN and the requirement
that every plugin's CMakeLists.txt *must* do MYSQL_ADD_PLUGIN
for PLUGIN_XXX=YES to work. This was very fragile and cannot be
relied on.

Use a different implementation of =YES check - iterate all
PLUGIN_* variables and see which one doesn't have a matching target.

Revert all ONLY_IF changes in CMakeLists.txt files.

we don't want mysys static data structures to be overwritten
when a dynamic plugin is loaded.

This reverts commit aa61e4c7
that broke the compilation on few platforms (e.g. centos5).

These warnings are already fixed properly in 10.0-connect.

workaround, not a fix: don't build key management plugins in yassl builds

when page compression and google encryption is used.

because old openssl versions (e.g. on labrador) don't have it

but do MyISAM first - to read mysql.plugin table

- Fixed compiler warnings
- Added include/wait_for_binlog_checkpoint.inc, as suggested by JonasO
- Updated 'build-tags' to work with git (Patch by Serg)

Added an extra column to i_s_applicable_roles, named IS_DEFAULT.
The column displays which role is the default role for the user
querying the table.

add missing plugins to debs

Adjust the configuration options, as discussed on the
maria-developers@ mailing list.

The option to hint a transaction to not be replicated in parallel is
now called @@skip_parallel_replication, consistent with
@@skip_replication.

And the --slave-parallel-mode is now simplified to have just one of
the following values:

  none
  minimal
  conservative
  optimistic
  aggressive

This reflects successively harder efforts to find opportunities to run
things in parallel on the slave. It allows to extend the server with
more automatic heuristics in the future without having to introduce a
new configuration option for each and every one.

(Without this, it happened for me that realpath() failed returning
undef for the default vardir. This in turn caused mysql-test-run.pl to
delete the source mysql-test/ directory.)

pool->threads is freed before being reassigned the new pool.

Although not really a memory barrier I though it prudent to keep the pool
thread count to be the lower of the old/new thread list before the new threads
is allocated.