MDEV-4444 Server crashes with "safe_mutex: Trying to destroy a mutex share->mutex that was locked" on attempt to recover an archive table

change WARN_PLUGIN_DELETE_BUILTIN to ER_PLUGIN_DELETE_BUILTIN

Patches provided by Jan Stanek and Honza Horak

reset SERVER_MORE_RESULTS_EXISTS *after* sending the OUT packet to the client.
the next packet will be the last one.

patch by Georg Richter.

fix the init script for .deb packages
(rpm's were fine already)

protect THD::db with THD::LOCK_thd_data

add a new command-line option --pam-use-cleartext-plugin

recognize the constant, to be compatible with MySQL clients.

backport mysql --binary-mode (bug#11747577, bug#33048)

Additional fix for remaining issues with sys_vars.* tests

MDEV-4468 Assertion `error != 0' fails or timeout occurs on select from a FEDERATED table which points at a non-existent table

Federated uses SHOW TABLE STATUS LIKE for ::info().
For nonexisting remote table it doesn't fail, but returns an empty result set.
We need to fake the error in the handler.

MDEV-4480 Assertion `inited == NONE' fails on closing a connection with open handler on temporary table

  (uninitalized variables are detected by DBUG builds)
- Fixed wrong declaration which cased compile failure on 32 bit

cmake/build_configurations/mysql_release.cmake:
  Added -Wno-uninitialized to avoid warnings in release builds
  (uninitalized variables are detected by DBUG builds)
include/maria.h:
  Fixed wrong declaration which cased compile failure on 32 bit
include/myisam.h:
  Fixed wrong declaration which cased compile failure on 32 bit

Fixed some cases that didn't work with > 4G buffers.
Fixed compiler warnings


include/mysql_com.h:
  Avoid compiler warning with strncmp()
sql-common/client.c:
  Fixed long comment; Added ()
sql/filesort.cc:
  Fix code to get filesort to work with big buffers
sql/sys_vars.cc:
  Fixed some cache variables that could be set to higher value than the size_t
  Limit query cache to ULONG_MAX as the query cache buffer variables are ulong
storage/federatedx/ha_federatedx.cc:
  Remove not used variable
storage/maria/ha_maria.cc:
  Fix that bulk_insert() works with big buffers
storage/maria/ma_write.c:
  Fix that bulk_insert() works with big buffers
storage/myisam/ha_myisam.cc:
  Fix that bulk_insert() works with big buffers
storage/myisam/mi_write.c:
  Fix that bulk_insert() works with big buffers
storage/sphinx/snippets_udf.cc:
  Fixed compiler warnings

-Run test suite with smaller aria keybuffer size (to make it possible to run more tests in parallel)
-Added test and extra code to ensure we don't leave keyread on for a handler table.
-Create on disk temporary files always with long data pointers if SQL_SMALL_RESULT is not used. This ensures that we can handle temporary files bigger than 4G.

mysql-test/include/default_mysqld.cnf:
  Run test suite with smaller aria keybuffer size
mysql-test/suite/maria/maria3.result:
  Run test suite with smaller aria keybuffer size
mysql-test/suite/sys_vars/r/aria_pagecache_buffer_size_basic.result:
  Run test suite with smaller aria keybuffer size
sql/handler.cc:
  Disable key read (extra safety if something went wrong)
sql/multi_range_read.cc:
  Ensure we have don't leave keyread on for secondary_file
sql/opt_range.cc:
  Simplify code with mark_columns_used_by_index_no_reset()
  Ensure that read_keys_and_merge() disableds keyread if it enables it
sql/opt_subselect.cc:
  Remove not anymore used argument for create_internal_tmp_table()
sql/sql_derived.cc:
  Remove not anymore used argument for create_internal_tmp_table()
sql/sql_select.cc:
  Use 'enable_keyread()' instead of calling HA_EXTRA_RESET. (Makes debugging easier)
  Create on disk temporary files always with long data pointers if SQL_SMALL_RESULT is not used. This ensures that we can handle temporary files bigger than 4G.
  Remove not anymore used argument for create_internal_tmp_table()
  More DBUG
sql/sql_select.h:
  Remove not anymore used argument for create_internal_tmp_table()

Problem : 
libreadline.so was already present on the machine, however the cmake check NEW_READLINE_INTERFACE was unsuccessfull indicating, thus bundled library had to be used instead of  system library.
The problem was that the value for HAVE_HIST_ENTRY cmake variable  was cached with incorrect  value (1 on NetBSD).

The fix is to change HAVE_HIST_ENTRY to 0 with  CACHE FORCE, after switching to bundled readline.

MDEV-4520: Assertion `0' fails in Query_cache::end_of_result on concurrent drop event and event executio

Fix for embedded library, where thd->net.vio is not set which efficently switched off QC in emmbedded server for previous patch.

remove the workaround from cmake/os/FreeBSD.cmake

MDEV-4520: Assertion `0' fails in Query_cache::end_of_result on concurrent drop event and event execution

If there is no net.vio then query cache cant't get data via net_real_write() so it is better just do not try to cache such query.

replaced snippets_udf.cc with the latest version (2.0.8 from sphinxsource.com), fixed trivial errors on Windows.
It will be compiled and installed into plugins directory now.

if qc->try_lock() fails, it's not an error

(part 2)

change maria.distinct to use a function that doesn't require ssl-enabled  builds

with query cache, charset ucs2 and collation ucs2_unicode_ci

  @ mysql-test/r/ctype_ucs2_query_cache.result
  @ mysql-test/t/ctype_ucs2_query_cache-master.opt
  @ mysql-test/t/ctype_ucs2_query_cache.test
    Adding tests

  @ sql/sql_cache.cc
    Fixing not to use default_character_set->state_map,
    which can point to a non-ASCII character set (utc2, utf16, utf32)
   and thus have state_map undefined.