* Instead, use separate SHOW commands for tables, functions, procedures and triggers
* Catch this chance to move these methods from main unit to mysql_connection, so they're accessible in a more generic way
* Additionally, introduce new classes TDBObject and TDBObjectList which provide a more generic way than TMySQLQuery to access these database objects.
Fixes issue #1529
* Use this chance to add a confirmation dialog when leaving the editors, to ask the user if he wants to save modifications. Fixes issue #1524.
* Also, enhance Mainform.RefreshTreeDB in a way that it does not trigger the OnFocusChange event. Important for the editors when saving changes.