add health images. damage is not applied yet
add gameover screen if health is nil. refactoring :+1:
fix. touch only if not already touched
fix spec
unused var
draw empty health. add level_object health which increase player hp
level_object health image
health spec
refactoring
Merge branch 'master' into health

Conflicts:
	game.rb
	lib/level.rb
	lib/player.rb
merge with master
refactoring after code review
refactoring after code review. specs have been extended with touched?
Merge branch 'master' into health

Conflicts:
	levels/1
merge with master
Merge pull request #6 from yratanov/health

add health images. damage is not applied yet