Fixes Hidden doors opening before closing

fixes #1600

Turns out the issue is that door:show() is getting called by [level.lua](https://github.com/CalebJohn/hawkthorne-journey/compare/hidden-doors?expand=1#diff-4029651f2a81cb287a78020be0d3aa94L312) when the door shouldn't actually be opening, and the only reason door:hide() is getting executed was because door:show() was called first and setting door.hidden to false.

I fixed this in a roundabout way of level checks but I think this shows that we may need to look into at least a little level persistence, so that doors such as this one can save their state.