cleaner require js integration

This pull request is related to https://github.com/EightMedia/hammer.js/pull/356. It fixes the problem @jantimon describes without adding the name while defining require modules.

The problem is that we need deferent abstractions of define for there three cases:

* Stand alone hammer.js
* Stand alone jquery plugin
* Merged hammer and jquery plugin

I've put the init function for the query plugin into a src file and added it to the build in order to prevent code duplication.

The whole thing feels a bit dirty so I'm open for suggestions to do it better. But as far as I can see this is the only way to have a clean requirer integration without naming modules or adding unused dependencies.

Cheers
Tobi