Re #60: Add UI to add/remove/edit weapons in GTK * Fix widget enabling/disabling (sometimes enabling ratio input for numeric limit) * Correct behaviour of Edit dialog (setting wrong value on edit) * Add setting of limits based on specific equipment item to base dialog controller * Make sure that we catch all radio button click events from Edit dialog * Add ability to ignore and listen to widgets to make sure that changes don't cascade TODO: See if code can be tidied up and common classes created