clean up the explain structure in this case.

Fix all suite.pm files that had errors and test files that were skipped because of that

* remove is_embedded.require

because some suites may be disabled unless a plugin is available,
and compiled-in plugins are only known after collect_mysqld_features().

Additionally move mysql_install_db() after everything else it's collected -
it's a slow process, better do it after all the information is gathered
(and reported to the user).

plugin.cmake does it automatically for all plugins

* rename "xtradb" combination to be called "innodb"
* disable xtradb_plugin embedded tests (because of RECOMPILE_FOR_EMBEDDED)

(it was used only for plugins in mysqld)

support ha_innodb.so as a dynamic plugin.
* remove obsolete *,innodb_plugin.rdiff files
* s/--plugin-load=/--plugin-load-add=/
* MYSQL_PLUGIN_IMPORT glob_hostname[]
* use my_error instead of push_warning_printf(ER_DEFAULT)
* don't use tdc_size and tc_size in a module

update test cases (XtraDB is 5.6.14, InnoDB is 5.6.10)
* copy new tests over
* disable some tests for (old) InnoDB
* delete XtraDB tests that no longer apply

small compatibility changes:
* s/HTON_EXTENDED_KEYS/HTON_SUPPORTS_EXTENDED_KEYS/
* revert unnecessary InnoDB changes to make it a bit closer to the upstream

fix XtraDB to compile on Windows (both as a static and a dynamic plugin)

disable XtraDB on Windows (deadlocks) and where no atomic ops are available (e.g. CentOS 5)


storage/innobase/handler/ha_innodb.cc:
  revert few unnecessary changes to make it a bit closer to the original InnoDB
storage/innobase/include/univ.i:
  correct the version to match what it was merged from

modified:
  storage/connect/odbconn.cpp

Fixing "/*100000 ...*/" comments (i.e. MySQL style with 6-digits),
which were unintentionally broken in the MDEV-5009 patch.

modified:
  mysql-test/r/comments.result
  mysql-test/t/comments.test
  sql/sql_lex.cc

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

The problem seems to be fixed by some earlier change
and is not reproducible any longer. Only adding a test case.

Fixed a wrong assertion.

Also known as MySQL#70047 and BUG#17316314 (srv_buf_size not declared).
The workaround is taken from MySQL 5.6 tree: 

  BUG#17316314 - SRV_BUF_SIZE NOT DECLARED
  Temporary fix. Disabling FALLOC_FL_PUNCH_HOLE for now

backporting from the main 10.0

modified:
  mysql-test/r/func_like.result
  mysql-test/t/func_like.test
  sql/item_cmpfunc.cc

Fixed.

modified:
  storage/connect/valblk.cpp

- Fix compiler warning in ODBConn::GetCatInfo

modified:
  storage/connect/odbconn.cpp