when looking for my.cnf files: if DEFAULT_SYSCONFDIR (or INSTALL_SYSCONFDIR)
is specified (for rpms it always is), use that instead of hardcoded /etc path.
includes:
* remove some remnants of "Bug#14521864: MYSQL 5.1 TO 5.5 BUGS PARTITIONING"
* introduce LOCK_share, now LOCK_ha_data is strictly for engines
* rea_create_table() always creates .par file (even in "frm-only" mode)
* fix a 5.6 bug, temp file leak on dummy ALTER TABLE