HUD Redesign - WIP

I've taken a stab at redesigning/simplifying the hud, with inspiration from #1439

* The potion effects notification have been replaced by small icons (invulnerability, high jump, extra punch damage etc.) though I hope someone can provide me with better images. Things like money/filled health are now signaled by sounds (which could also be improved). Flashing/words will be removed once the spacing pull has been merged.
* If you have an active quest, there will be a Q displayed in the HUD (I know @8bitgentleman is working on an overhaul of the quest system so I haven't done much here but I think we agreed the hud wasn't the place to display the details of the quest)
* Generalised the boss HUD
* Redesigned the auto-save warning & autosave pop-up

![image](https://cloud.githubusercontent.com/assets/2385512/4519561/5c22e39a-4cc1-11e4-9c95-38e9fe6f7ac6.png)