update 0.1.3

A decent sized update, most notably adding an options menu that currently only lets you change a few difficulty - related values:

+ added the difficulty options, accessible from the main menu under the orange cog logo. You can turn off last updates shield cells, turn of the natural shield regen, or, if you really hate winning, you can turn on no-hit mode, disabling the shield entirely.

~ when near the player, shield cells will now float towards you quickly, like pickups in most other games

~ resprited the android to look a little more... android like