ENYO-437: Add MarqueeSample to package.js

### Issue
`MarqueeSample` was missing from the `package.js` file for Moonstone samples.

### Fix
`MarqueeSample` has been added, and as a bonus, double-quotes have been converted to single-quotes.

Enyo-DCO-1.1-Signed-off-by: Aaron Tam <aaron.tam@lge.com>