Use SESSION TABLE_HANDLER as default table handler if given table handler doesn't exists


Docs/internals.texi:
  Updated description for how DATE, TIME and TIMESTAMP are stored
mysql-test/r/create.result:
  New tests
mysql-test/t/create.test:
  New tests
sql/handler.cc:
  Use SESSION TABLE_HANDLER as default table handler if given table handler doesn't exists.
sql/sql_parse.cc:
  Fix that we return hostname instead of IP in SHOW PROCESSLIST
sql/sql_show.cc:
  Print right hostname or IP in SHOW PROCESSLIST