Feedback incorporated!

This update primarily addresses the remaining feedback from the Indie City Games demo day, which were generally the more difficult to implement.

+More visual damage feedback added.   Rainbow sparks fly off your ship every frame you are in damagestate.  I'm really happy I found an excuse to add more rainbows.

+Shop and similar menus are now mouse navigable.  Click on an item to select it, click on an already selected item to buy/sell/accept it.

+Weapon 16, the Pulse Blazor, is now  visible for 6 frames.  This was crudely achieved by making the beam use less energy, and thus remain on for a longer burst.

+Respawn menu  takes time off the respawn for each correct answer

+/-  I still haven't played "SPAZ", "SPAZ 2", or "Heat Signature", but I've looked at videos of gameplay for them.  I might implement some of the more strategic gameplay at some later time, but for now you'll just be looking after one ship. 

 The next big task is to streamline my menu code and make many of the  recent changes (and more!) into options.  Also high on my list is to pick or create a starter system that is relatively tame for the new players.