Title Screen and some new controls

The work on the new UI is in progress, but I added a few updates to the current one.

• Right Mouse Click cancels everything but movement.
• Keyboard controls: Enter confirms, Escape cancels (backspace and delete work, too)
• Title screen and tutorial have been updated and simplified a bit.

The HUD itself still needs updates, and I have to speed up my testing process. It's a little bit at a time.

New demo night was announced: May 21. Less than a month to get the new UI ready.