Port binlog_bytes_written status to 5.6

Summary:
Add to SHOW GLOBAL STATUS the counter Binlog_bytes_written that counts
all (or most) bytes written to the binlog. Also, change per-user counter
updates to not use atomic ops as LOCK_log is held during all increments.

Test Plan: mysqltest.sh

Reviewers: steaphan

Reviewed By: steaphan
Porting per session stats from 5.1 to 5.6

Summary:
Collect the following status variables (including some new ones)
per-session with global rollup: Collect_stats_seconds (new), Command_seconds,
Exec_seconds, Open_tables_seconds (renamed), Parse_seconds, Pre_exec_seconds,
Read_requests (new), Read_seconds (new).

Test Plan: mysqltest.sh

Reviewers: steaphan

Reviewed By: steaphan
Port per query stats from 5.1 to 5.6

Summary:
Make the log-slow-extra counters per query in the slow query log

Test Plan: mysqltest.sh

Reviewers: steaphan

Reviewed By: steaphan
Porting more table stats changes from 5.1 to 5.6

Summary:
Improved the determinism of some table stats tests.

IO stats collected with table space split between secondary and PK indexes.

Add an queries_empty column in information_schema.table_statistics.
Only select queries are considered so far, as the empty queries in
IS.user_statistics.

Test Plan: mysqltest.sh

Reviewers: steaphan

Reviewed By: steaphan
port global per page IO stats from 5.1 to 5.6

Summary:
Adds stats per page type for all page types defined in
storage/innodb_plugin/include/fil0fil.h:131-144

Test Plan: mysqltest.sh global_page_stats

Reviewers: akotulski

Reviewed By: akotulski
Porting secondary index to 5.6

Summary:
Add counters to show global status for InnoDB. The counters are:

Innodb_secondary_index_record_read_check 8878
this is the number of times the visibility check was done for a secondary
index access.

Innodb_secondary_index_record_read_sees 8878
this is the number of times the leaf page does not require reading the
row from the clustered index to determine visibility

Test Plan: mysqltest.sh

Reviewers: steaphan

Reviewed By: steaphan