0.31 Release

This version was long in the baking. And also the game is finally playable and fun again! That wasn't the case since 0.23.

• Removed infinite map. You play in acts again. For now the game ends at the end of act 1.
• The railroad is more interesting now. You get a gem every 2 intersections, get a new cart half way through, and fight a miniboss before the end.
• Added a new boss system but I'll rework it later
• Cannot merge carts during combat anymore. Back to only merging in cities.
• Gems are now more interesting. But not all gem effects are implemented yet.

• Enemies don't carry gems or player guns anymore. Enemies are also more random. Enemies carry "unique gear" to make every encounter feel different. Although currently there are only a few unique gear. Later they will be stuff like "flip left and right button", or other confusing effects.
• Removed difficulty increasing over time, then added it back as difficulty increasing with every intersection.
• So. Many. Bug. Fixes. Also gamepad is playable again, which needed some additions like finer item selection. There are still some bugs but no game breaking bugs anymore as far as I can see.