Fixed bug on function call when InnoDB plugin is used.

option leaves the database in inconsistent state,

Analysis: Problem was that atomic writes variable had incorrect
type on same places leading to fact that e.g. OFF option was
not regognized. Furthermore, some error check code was missing
from both InnoDB and XtraDB engines. Finally, when table is
created we have already created the .ibd file and if we can't
set atomic writes it stays there.

Fix: Fix atomic writes variable type to ulint as it should be.
Fix: Add proper error code checking on os errors on both InnoDB
and XtraDB
Fix: Remove the .idb file when atomic writes can't be enabled
to a new table.

Removed: innodb_use_lz4 configuration parameter

Added: innodb_compression_algorithm configuration parameter
0 = no compression, 1 = ZLIB, 2 = LZ4, 3 = LZO

Fixed issue with incorrect trim calculations

asserts can be conditionally compiled out.

see MDEV-5981

another post-fix patch for MDEV-5850: MySQL Bug#21317: SHOW CREATE DATABASE does not obey to lower_case_table_names
(for case-insensitive filesystems)

sql/events.cc:
  for "SHOW EVENTS IN db_name"
sql/sp_head.h:
  for "CREATE EVENT", and everything SP-related
sql/sql_acl.cc:
  privilege check for mysql_change_db()
sql/sql_db.cc:
  for metadata locking of db names
sql/sql_parse.cc:
  any_db is a constant, it is not writable
sql/sql_show.cc:
  for SHOW CREATE TRIGGER and other trigger-related statements

MDEV-5971 Asymmetry between CAST(DATE'2001-00-00') to INT and TO CHAR in prepared statements

Consistently set maybe_null flag, even not-NULL temporal literal may become NULL
in the restrictive sql_mode.

fix uninit variable

Fixed that the we don't change CREATE to CREATE OR REPLACE, except if the slave removed an existing table as part of CREATE.
This will help the following replicaition scenario:
MariaDB 10.0 master (statement replication) -> MariaDB 10.0 slave (row based replication) -> MySQL or MariaDB 5.x slave


mysql-test/r/mysqld--help.result:
  Updated help text
mysql-test/suite/rpl/r/create_or_replace_mix.result:
  Added more tests
mysql-test/suite/rpl/r/create_or_replace_row.result:
  Added more tests
mysql-test/suite/rpl/r/create_or_replace_statement.result:
  Added more tests
mysql-test/suite/rpl/t/create_or_replace.inc:
  Added more tests
sql/handler.h:
  Added org_options so that we can detect what come from the query and what was possible added later.
sql/sql_insert.cc:
  Only write CREATE OR REPLACE if was originally specified or if we delete a conflicting table as part of create
sql/sql_parse.cc:
  Remember orginal create options
sql/sql_table.cc:
  Only write CREATE OR REPLACE if was originally specified or if we delete a conflicting table as part of create
sql/sys_vars.cc:
  Updated help text

            TABLE_SHARE::visit_subgraph

tc_acquire_table() is not ready to update TABLE::in_use without mutex:
thr1: table= free_tables.pop_front(); // table->in_use is 0
thr2: tdc_remove_table();
thr2: find_deadlock(); // assert(table->in_use != 0)
thr1: table->in_use= thd;

Protect update of TABLE::in_use by LOCK_table_share.

mysql.column_stats.

- Fix valgrind failure: don't touch table_list->master_had_triggers 
  when RBR_TRIGGERS is not compiled in.

post-fix patch for MDEV-5850: MySQL Bug#21317: SHOW CREATE DATABASE does not obey to lower_case_table_names

- Show a line with "Engine-independent statistics collected" when ANALYZE command
  caused EITS statistics to be recollected.

  to use named pipe on Windows by specifying the host as '.'
  This addresses MDEV-5952.
modified:
  storage/connect/myconn.cpp

- Clean some unused code
modified:
  storage/connect/connect.cc
  storage/connect/connect.h
  storage/connect/ha_connect.cc
  storage/connect/ha_connect.h

- Dont substract unsigned numbers, use correct calculations.
- (there is no testcase because effort is required to come up with it)

- Move [some] engine-agnostic tests from t/selectivity.test to t/selectivity_no_engine.test
- Move Histogram::point_selectivity to sql_statistics.cc