In response to Issue #148 Wrap cmb.js inside namespace object to prevent conflicts

This patch just wraps all the functions in cmb.js inside the CMBMeta object to prevent conflicts with other plugins using similar functions.  For instance we were declaring some of our variables in the global namespace and it conflicted with the Woo Themes Media Upload js.

*Note*: The commit I'm sending this pull request for is dacb6d8.