firebird: enable-debug cause trouble due to a lifecycle management issue

firebird in debug mode abort() on lo shutdown due to a lifcycle management
issue where firebord try to create a directory in a temp directory that
is not there anymore, and then exception for it and
that exception in debug mode cause an abort.

Change-Id: Iabbd6ffda34a84e5b0d8e44761226083c8c1d168
firebird driver, abandon ref to about to be disposed embedded storage.

Change-Id: I6bfce155151b79cd0a1707744e79298b45d8752b
firebird: release driver on dispose rather than destroy.

Change-Id: I5ffeaf818c1eb4985bdd150830f089f03fe42ceb
firebird driver: shutdown explicitely firebird on dispose of driver.

Change-Id: Ia44f7e01a3a01da57e4d9382f41511aa6f987b43