Indie Game Nation fixes 2

Finishing the main stuff that was noticed at Indie Game Nation, as well as some fixes I've wanted to do for a long time. 

-fix for when the chest goes in the ground due to low framerates or whatever other reason

-fixed a bug where the player couldn't jump after picking up the chest

-fixed custom controls display with specific keys. also prevented some keys like backpsace and escape from being selected

-updated the sprite of semisolid platforms

-changed the appearance of the nautilus' ink breath

-added a first npc, which doesn't do much for now, but hey it's a start.

I also started setting up a steam page for the game.