Upgraded uglify and Travis CI integration

Updates to the latest version of uglify and adds Travis CI integration to guarantee that the file is properly minified.

Better debug

Improve debug in development mode, logging when there's a module that was expected to load but was not found.

Undefine

Add new method undefine

Fix multiple async-amd load conflict

Merge pull request #5 from elo7/fix-define

[fix-define] Checks whether the function define already exists