Less deprecated code

Make current thread and frame requirements a part of the GDB command object, so the controller can take over setting this in gdb as required. This should make the debugger less error prone in the new model/view code.

Start on new way of providing specialised debugging views for certain objects - first example is parsing of QString (not yet working). One day soon you should be able to write customised views using plugins, that's going to be awesome :)