update v0.1.5

Bit of a bigger one.

• Added flash effect when taking damage!
• More stuff to make controllers feel better.
• Added the ability to go back to the main menu without closing the entire game. (It's one of those things you don't notice in games unless it's not there).
• Made demolishing buildings have a confirmation prompt to reduce tears.
• Fixed screen wrapping code to better handle something being on the other side.
• "Fixed" a "rare" bug where you would spawn inside an object. If it still happens please let me know.
• Shuffled around mantis ship's prices and power levels.
• Probably added some more effects and tweaks and changes but I can't remember them all.