Fix three.js source URL

 * Use https://rawgithub.com/ instead of https://raw.github.com/ to avoid
   MIME type errors on Chrome.
 * Fix three.js library file name.
Fix deprecation warning.

Deprecation warning:

  .setClearColorHex() is being removed. Use .setClearColor() instead.
Merge pull request #1 from potomak/master

Minor updates