Fixed a letter-casing issue with the Moonstone Sampler's CSS filename.
It should now be loadable on case sensitive systems.

Enyo-DCO-1.1-Signed-off-by: Blake Stephens <blake.stephens@lge.com>
Merge pull request #1764 from enyojs/fix-SampleFileCase-blakestephens

Fixed a letter-casing issue with the Moonstone Sampler's CSS filename.

Integrated-By: Aaron Tam (aaron.tam@lge.com)