Discover P_S tables automatically.

Most of this patch is code clean-up:
- removed tests and code responsible for P_S tables correctness verification
- always return error from ha_perfschema::create()
- install/upgrade scripts won't create P_S tables anymore

MySQL 5.6.10 performance schema: merge of host_cache table

- mdl.cc and mdl.h merged completely
- mysql_system_tables*.sql merged completely
- Fixed wrong merge of lock_tables
- Added some missing functions:
 - bool THD::notify_shared_lock()
 - Dynamic_array::pop, Dynamic_array::del
- Added MDL_context_owner to THD
- Added metadata_locks_hash_instances

Moved out creation of performance schema tables from mysql_system_tables.sql as
the performance_tables creation scripts needs a working mysql.proc to work.

client/mysql_upgrade.c:
  Added option -V, --version
debian/dist/Debian/mariadb-server-5.5.files:
  Added mysql_performance_tables.sql
debian/dist/Ubuntu/mariadb-server-5.5.files:
  Added mysql_performance_tables.sql
mysql-test/lib/v1/mysql-test-run.pl:
  Added mysql_performance_tables.sql
mysql-test/mysql-test-run.pl:
  Added mysql_performance_tables.sql
scripts/CMakeLists.txt:
  Moved out creation of performance schema tables from mysql_system_tables.sql 
  as the performance_tables creation scripts needs a working mysql.proc to work
scripts/mysql_install_db.sh:
  Added mysql_performance_tables.sql
scripts/mysql_performance_tables.sql:
  Moved out creation of performance schema tables from mysql_system_tables.sql 
  as the performance_tables creation scripts needs a working mysql.proc to work
scripts/mysql_system_tables.sql:
  Move creation of performance schema tables to mysql_performance_tables.sql
  Added 'flush tables' to get things to work if someone deletes a table like mysql.proc before run
scripts/mysql_system_tables_fix.sql:
  ove performance table things to mysql_performance_tables.sql
storage/perfschema/pfs.cc:
  Fixed comment