Added audio assets
Worked on Bird Hero Intro
Changed how buttons are created
Changed buttons again, more flexible

You are now able to use several representations on the same button.
Updated to Phaser from dev branch
Birdhero: Make it rain!
Use new cover object in other places
Removed unnecessary code
Kill tweens when state is changed
An easy way to add sounds to tweens
Birdhero: Introductory instructions
Bugfix for addSound
Birdhero: added agent intros
Merge branch 'master' of https://github.com/unholyhen/mWorld into unholyhen-master

Conflicts:
	src/js/states/subgames/BirdheroGame.js
Merge branch 'unholyhen-master'
Mergefix: Functions got doubled in the merge
Bugfix for addSound

There were issues with pausing when putting timelines in timelines, so
instead we use sound duration. However, sound duration is tricky
business and this solution is prone to be filled with bugs.
Birdhero: Better scripting
Balloons attatch to the basket and make it fly higher.

Also added buttons, the left one not working as intended yet. Rewrote
the tweens to use timelineMax.