MDEV-5124 cmake failure when fullhostname is not resolved

expand fullhostname inside the string, to have an empty string, not nothing,
when fullhostname is not defined
MDEV-4977 ./mysql-test/mysql-test-run.pl not identifying mariadb version

quote the path when using it in a regex - the path might contain wildcards (e.g. +)
MDEV-5054 Failing test(s): main.mysqld--help sys_vars.character_sets_dir_basic

fix tests where a path was used as a regex.
revert changes to sys_vars.character_sets_dir_basic - we don't run it on windows anyway
MDEV-5030 RPM installation not running mysql_install_db if datadir exists

before running mysql_install_db check for the existence
of $datadir/mysql, not simply $datadir ($datadir might be mounted on
a separate device - exists, but empty)
MDEV-5022 Strange message or wrong errno on mismatching versions of plugin and server

1. use an appropriate errno code
2. put a comma between the errno and the error message text
MDEV-5186 /usr/bin/mysqld_safe doesn't have NUMA options support

port mysqld_safe numa extensions from percona-server: --flush-caches and --numa-interleave
MDEV-5101 INFORMATION_SCHEMA.PROCESSLIST reports an incorrect value for Time for connecting threads

by convention query execution time should be 0 if its start_time is 0
(this was lost when fixing MDEV-4578)
MDEV-5116 MariaDB upgrade breaks replication

mysql_upgrade should do --skip-write-binlog by default
- Add (limited) support for UPDATE and DELETE to ODBC tables
  (also provide the possibility to issue NOTE warnings)

modified:
  storage/connect/connect.cc
  storage/connect/ha_connect.cc
  storage/connect/ha_connect.h
  storage/connect/odbconn.cpp
  storage/connect/odbconn.h
  storage/connect/plgdbsem.h
  storage/connect/tabodbc.cpp
  storage/connect/tabodbc.h

- Return proper error number when modifying read only tables

modified:
  storage/connect/connect.cc
  storage/connect/ha_connect.cc
  storage/connect/ha_connect.h
  storage/connect/mysql-test/connect/r/bin.result
  storage/connect/mysql-test/connect/r/csv.result
  storage/connect/mysql-test/connect/r/dbf.result
  storage/connect/mysql-test/connect/r/fix.result
  storage/connect/mysql-test/connect/r/ini.result
  storage/connect/mysql-test/connect/r/vec.result
  storage/connect/mysql-test/connect/t/bin.test
  storage/connect/mysql-test/connect/t/csv.test
  storage/connect/mysql-test/connect/t/dbf.test
  storage/connect/mysql-test/connect/t/fix.test
  storage/connect/mysql-test/connect/t/ini.test
  storage/connect/mysql-test/connect/t/vec.test
  storage/connect/table.cpp
  storage/connect/taboccur.cpp
  storage/connect/tabpivot.cpp
  storage/connect/tabutil.cpp
  storage/connect/tabwmi.cpp
  storage/connect/tabxcl.cpp
MDEV-5241: Collation incompatibilities with MySQL-5.6
A clean-up: removing the code catching collation incompatibilities
from handler::check_collation_compatibility(), as the collation IDs
are already replaced at this point by TABLE_SHARE::init_from_binary_frm_image.
#90 debug long fsync system calls
MDEV-4435 Server crashes in my_strcasecmp_utf8 on ADD KEY IF NOT EXISTS with implicit name when the key exists.
        Use field name as a key name if the key name wasn't specified.
MDEV-5103: server crashed on singular Item_equal

Singular Item_equal support added.

The problem was that during constant table substitution Item_equal become containing only one constant which was not supported internally.
MDEV-4824 userstats - wrong user statistics
(and valgrind warnings)

* move thd userstat initialization to the same function
  that was adding thd userstat to global counters.
* initialize thd->start_bytes_received in THD::init
  (when thd->userstat_running is set)
MDEV-5153: Server crashes in Item_ref::fix_fields on 2nd execution of PS with LEFT JOIN and MERGE view or SELECT SQ

1. Transformation of row IN subquery made the same as single value.
2. replace_where_subcondition() made working on several layers of OR/AND because it called on expression before fix_fields().
MDEV-4436 CHANGE COLUMN IF EXISTS does not work and throws wrong warning.
        Use sql_field->change parameter as the name of the field.
mark ft-index cmake variables as advanced
MDEV-5236 Status variables are not all listed alphabetically

sort Com_ counters. No simple fix for Binlog_ variables.
- Add (limited) UPDATE/DELETE support to MYSQL type CONNECT tables

modified:
  storage/connect/ha_connect.cc
  storage/connect/tabmysql.cpp
  storage/connect/tabmysql.h
  storage/connect/tabodbc.cpp
merge 5.3->5.5