* change Firebird left/right field delimiters to double-quotes

Firebird prefers double-quotes for field delimiters (there are cases where you can use no quotes but double-quotes are always acceptable except when specifically choosing the outdated (and non-default) dialect of 1); using empty field delimiters was causing the transition to embedded firebird for Mastery@Work to fail until I wrapped the relevant classes up in facades to produce the desired effect. It would be great if I could just dump that code for an official implementation.