* Add support for the LineTool and RectTool while in the EditorMode to
easily draw straight lines and rectangle outlines.
* Key bindings were added to toggle tools in lieu of a proper UI to
select the tool from a toolbar.
* "F" for Pencil (Freehand) Tool (since "P" is for "Playtest")
* "L" for Line Tool
* "R" for Rectangle Tool
* Fix the EditorUI not showing the correct palette baked into the level
and only showing the default. This was tricky because the palette UI
can only be configured at setup time but not updated later.
* Add a new default palette for the Blueprint theme. Blueprint has a
dark background, so the palette colors should be bright. This palette
is chosen when you start a map with the blueprint wallpaper.
* Add a background Canvas to the MenuScene. In the "New Level" screen,
the background canvas will update to show the wallpaper settings
you've chosen as a preview of the level theme you're about to create.