Implements the dev console in-game with various commands to start out
with.
Press the Enter key to show or hide the console. Commands supported:
new
Start a new map in Edit Mode.
save [filename.json]
Save the current map to disk. Filename is required unless you
have saved recently.
edit filename.json
Open a map from disk in Edit Mode.
play filename.json
Play a map from disk in Play Mode.
