A fairly large update

Yes it's another update, they probably won't be quite this quick from now on, maybe once a week or so.

This time I've added a new unit, the Alien Laser Unit. This is now the top level unit in the game. I also took the opportunity to move some of the other units around, as interesting as the miner is - it just isn't as dangerous as the Shooter or Hunter, so I moved it down a few places.

I've also put an in-game menu in place, pressing escape will bring it up and let you change some settings, or just pause or quit the game. One option that won't make a difference in-game (see how I linked those) is the new skip tutorial levels button.

If you turn this on it will skip right to level 3, ignoring the level with no enemies and the level with asteroids, both aren't challenging and are really just practice for the controls.

The Laser was going to be a test of the particle effects I intend to put in the game once I've got it working well, but it progressed so well that I decided to add it in.

Thanks for playing