* Show line and column on "Preprocessed" tab
* Properly disable unvailable (context) menu items and buttons in the button bar
* Perform actions of (context) menu items and button bar buttons on the active tab (if action is available) instead of always on the possibly hidden editor tab
* Search/Replace and Goto Line floaters work on the active tab instead of always on the possibly hidden editor tab
This should fix the run off segment bugs by not overriding LLTextBase::clearSegments() in LLTextEditor
TODO: Move the rest of the script stuff out of LLTextEditor for simplicity sake