(Work in progress)

Enemies won’t damage the player on every game update
Merge branch 'master' into player-immune-after-damaged

Conflicts:
	js/game.js
	js/player.js
Spiders use same damage logics as trolls

*Also changed invulnerability timer to 1 sec instead of 300 ms
Merge pull request #67 from MrMagnus/player-immune-after-damaged

Player immune after damaged
Merge pull request #64 from scmx/level-specific-backgrounds

Add support for level specific backgrounds
Merge pull request #65 from scmx/add-panel-view-class

Add PanelView constructor for easier rendering
Add OverlayView constructor

For creating views that can be activated/inactivated