Document 3rd party references

[thegsm]

Add to this issue any third party references and license you use so we can track this.
So far from quick search this is what I found:
Name: HOTween
Type: Source code
Source URL: http://code.google.com/p/hotween
License URL: http://www.holoville.com/hotween/license.html
Site URL: http://www.holoville.com/hotween/
License: MIT
Version: ??

Name: InControl
Type: Source code
Source URL: https://github.com/pbhogan/InControl
License URL: https://raw.github.com/pbhogan/InControl/master/README.markdown
License: MIT
Version: 1.1?

Name: GUIhover.wav
Type: Audio
Source URL: http://www.freesound.org/people/lebcraftlp/sounds/192275/
License URL: http://www.freesound.org/people/lebcraftlp/sounds/192275/
License: CC BY 3.0

[ghost]

Name: FredokaOne-Regular.ttf
Type: Font
Source URL: https://www.google.com/fonts/specimen/Fredoka+One
License URL: http://scripts.sil.org/cms/scripts/page.php?site_id=nrsi&id=OFL
License: SIL Open Font License, 1.1

[thegsm]

@MichaelFirman agreed we use the image in #174 under the condition that "it remains a non-commercial product endorsed by the studio/Hackett, and that I am credited if there are credits."

Adding this note to we'll be sure to include it as requested (because it wasn't added as a pull request)

[Cheeseness]

I added a LICENCE file today. This is where this stuff should be documented (since we're pushing out more regular builds now, that's probably a fairly high priority).