Implement random Color generation
Update file
Add custom seed for random numbers
Add new options to random color generation
Tweak random color generation
Move SeededRandom into CesiumMath
Randomize alpha component
Add unit tests for random color generation
Merge branch 'master' into random-color
Finish up random color generation.
Copy fixes from ab257e79501628190a3f7853df88da647a5cbef2

Also use Color.fromRandom in this example.
Update LICENSE.md and CHANGES.md
Clean up license comments.
Add license comments, and comment out unneeded code.
Match Math.random by using the range [0, 1) instead.
Fix typos.
Use .toBeBetween matcher function.
Merge pull request #1062 from AnalyticalGraphicsInc/random-color

Color.fromRandom
The license for mersenne-twister was added to the wrong location.
Merge branch 'master' of https://github.com/AnalyticalGraphicsInc/cesium into buildUpdate