#138: chaining .then() calls together now works as expected

I made the change discussed in #138 and ran grunt to copy/minify appropriately.  I then tested on the codebase where I originally discovered the error and everything works now.

This pull request does not include bumping the current version number or anything like that, since I thought it would be presumptuous of me to do that.  However, I would greatly appreciate a new release with this fix as soon as possible, so that bower can automatically pull down a fixed version.  I can make a separate pull request for that, or edit this pull request to include that, if either of those are desirable.