Now when a table is dropped the statistics on the table is removed 
from the statistical tables. If the table is altered in such a way
that a column is dropped or the type of the column is changed then
statistics on the column is removed from the table column_stat.
It also triggers removal of the statistics on the indexes who use
this column as its component.

Added procedures that changes the names of the tables or columns
in the statistical tables for. 
These procedures are used when tables/columns are renamed.

Also partly re-factored the code that introduced the persistent
statistical tables.

Added test cases into statistics.test to cover the new code.

mysql.column_stat, mysql.table_stat for the type DECIMAL(12,4).
When cached the values from these columns are multiplied by factor 10^5
and stored as ulong numbers now. 

The bug was the result of the incomplete fix for bug lp bug 1008293.

the new file is fully synced to disk and binlog index. This fixes a window
where a crash would leave next server restart unable to detect that a crash
occured, causing recovery to fail.

MDEV-359: Fix another case where switch-off semisync could cause a race that ended with server crash.

This one was when the code releases and reaquires the lock with pthread_cond_wait() - and semisync is switched off meanwhile.

The semisync code does a fast-but-unsafe check for enabled or not without lock,
followed by a slow-but-safe check under lock. However, if the slow check failed,
the code still referenced not valid data (in an assert() expression), causing a
crash.

Fixed by not running the incorrect assert when semisync is disabled.

This is XtraDB bug lp:1015109, introduced by innodb_split_buf_pool_mutex.patch

Comment the offending assertion, until the fixed XtraDB is available

MySQL introduced a class Deferred_log_events. This class keeps a pointer
last_added. The code was keeping this pointer around even after the memory
pointed to was freed, and later comparing the bogus pointer against other
allocated memory. This is illegal, and can randomly produce false equal
comparisons depending on whatever the malloc() subsystem decides to return.

- put back the result encoding in func_in.result (messed up by kdiff3)
- update .result for other tests (checked)

Virtual columns of ENUM and SET data types were not supported properly
in the original patch that introduced virtual columns into MariaDB 5.2.
The problem was that for any  virtual column the patch used the 
interval_id field of the definition of the column in the frm file as
a reference to the virtual column expression.
The fix stores the optional interval_id of the virtual column in the
extended header of the virtual column expression. 

Attempt to make it easier to upgrade mysql->mariadb on Ubuntu precise.
It looks like we were missing conflicts: and replaces: on packages
mysql-server-5.5 and mysql-client-5.5.

make sure that find_date_time_item() is called before agg_arg_charsets_for_comparison().
optimize Item_func_conv_charset to avoid conversion if no string result is needed

On localized Windows versions, Windows uses localized time zone names and contain non-ASCII characters.  non-ASCII characters appear broken when displayed by clients
The fix is to declare system_time_zone variable to have UTF8 encoding and to convert tzname to UTF8.

mysql-test/suite/sphinx/sphinx.result:
  Removed sphinx_time, as it was depending on timing.
mysql-test/suite/sphinx/sphinx.test:
  Removed sphinx_time, as it was depending on timing.