Removed const declarations to get rid of compiler warnings. The changes are similar to what is done in innobase in MySQL 5.5

BUILD/SETUP.sh:
  By default, build also with innodb-plugin
mysql-test/mysql-test-run.pl:
  Also search in lib64 directory for plugins (This is used at least on OpenSuse 12.1 when using default build scripts)
mysql-test/r/lock_multi.result:
  Allow test to be re-run even if it crashed.
mysql-test/t/lock_multi.test:
  Allow test to be re-run even if it crashed.
scripts/make_binary_distribution.sh:
  Ensure that libexecdir is named libexec (was not on OpenSuse 12.1)
scripts/mysql_config.sh:
  Fixed detection of lib64 was used.

This also fixes a (not likely) crashing bug when forcing a thread that was doing a table lock to re-open it's files, for example by creating a trigger.


mysys/thr_lock.c:
  Added more checking to find wrong locks.
  Removed one, not needed, parameter to thr_lock
sql/lock.cc:
  Fixed mysql_lock_tables() to retry with new sql_lock if lock fails. This was needed as table may be closed and reopened between retry's and then the old sql_lock will point to stale data.
sql/mysql_priv.h:
  Updated prototype
sql/sql_base.cc:
  Ensure that all tables are closed if opening of system table failes; This fixes the assert in THD::restore_backup_open_tables_state
sql/sql_handler.cc:
  Updated variable type

always try to use valgrind headers in debug builds.
define HAVE_valgrind for --with-valgrind
fix valgrind check in my_valgrind.h

 execution which mtr --embedded does not support

Sort counters by their names (otherwise, the order of SHOW STATUS output is sometimes sorted and sometimes not)

 Handler_mrr_key_refills, Handler_mrr_rowid_refills.

UNIX_TIMESTAMP() can be null, and returns null for invalid values

Fixed compiler warnings found by buildbot

Makefile.am:
  Removed extra empty line
cmd-line-utils/libedit/sys.h:
  Fixed that strndup() doesn't give compiler warnings
mysql-test/Makefile.am:
  Fixes for 'make distcheck'
plugin/auth_pam/auth_pam.c:
  Ensure that prototype for strndup() is included on linux
sql/share/Makefile.am:
  Fixes for 'make distcheck'
storage/innodb_plugin/btr/btr0sea.c:
  Fixed compiler warning
support-files/Makefile.am:
  Fixes for 'make distcheck'

mysql-test/suite/innodb_plugin/t/innodb_gis.test:
  Don't run test if innodb_plugin isn't used.

sql/signal_handler.cc:
  Added missing signal values.

Fixed supression in mysql-test-run so it also works on windows.

mysql-test/mysql-test-run.pl:
  Fixed supression so it also works on windows.
mysql-test/valgrind.supp:
  More general handling of memory loss in dlclose (backported from 5.2)
sql/signal_handler.cc:
  Added newlines around link to how to do bug reports

- MySQL 5.5 introduced caching of constant items by means of 
  wrapping them in Item_cache_XXX objects. If a subquery was wrapped
  in this cache, it could end up being pushed down by ICP.
- The fix is to add Item_cache::walk() which lets ICP to see that 
  the cache item has a subquery inside it, and disable pushdown for this case.

- In MySQL 5.5, print_join() was re-worked to print "FROM dual" when all
  tables are constant. This change didn't work together with table 
  elimination.

"relocation R_X86_64_PC32 against `handler_index_cond_check' can not be used when making a shared object; recompile with -fPIC"
don't use visibility=hidden for external functions

"safe exception patch".
Remove misleading comments suggesting about signal() Windows, the routine here
is part of a exception handler, and sig parameter is an exception code.

- In mi_rkey(), do correct handling of case where mi_yield_and_check_if_killed() 
  detects that the thread was killed (all other similar functions in MyISAM/Aria have 
  slightly different code and do not have this problem).
- Also fixed assignment in DBUG_ASSERT
- this is 2nd variant of the fix:
   = make .result file smaller
   = run KILLable statements in a separate connection, otherwise we could end up trying to 
     KILL the final "DROP TABLE" statement

mysql-test/suite/innodb/t/innodb_bug51920.test:
  Add another possible connect error

Fixed README with link to source
Merged InnoDB change to XtraDB

README:
  Added information of where to find MariaDB code
storage/archive/ha_archive.cc:
  Removed memset() of rows, a MariaDB checksum's doesn't touch not used data.