Health meter, also spikes do damage now :D

I cobbled together a health meter of sorts, and made spikes do damage to the player via triggers. 

I'd *really* like to be able to stop the player physics on death somehow, because the inertia seems to persist through Player Move Cancel and Player Set Position events, and I'm not sure how to properly change scenes yet (changing scene to the same scene just fades the screen out and I still have to learn how to actually properly do it).