UI done

OK, the UI is more or less frozen. We have a game over screen. Now I can focus on the game dynamics. I set a new goal: metabolize a fixed amount of pyruvate before your ATP runs out. Need to see what are challenging start values for each.

There still seem to be some bugs in translation of proteins. Also I still think the game is too hard for people with no background in biology. Will try to get some people to test play over the weekend.

Tasks:

* improve gameplay

* package so that others can test