Add complete parameter editing to the script editor

[jonko0493]

Adds the ability to edit all script command parameters (except for the chess-related parameters which are still poorly-understood).

Also adds some other neat things:

• A "searchable text" field to make searching through files easier -- might redo how this is done at some point but was useful
• Bugfix for the NONE selection crash
• Fixes a macOS context menu crash (probably)
• Adds Dialogue Properties items
• Adds the background palette effects to the preview (with color matrices!!)
• Adds a "background export" button to the background editor, allowing for exporting images
• Adds new RE info to the topic & group selection editors
• Adds half-width text replacement to most files (TODO: conditionalize it on config)
• Adds auto-nice quotes to text editors
• Fixup tab context menus to work on tabs

[WiIIiam278]

Thoroughly awesome work!!