Support for node/browserify

[mwiencek]

Fixes two compatibility issues:

1. Inside wrapped browserify modules, this does not refer to window,
   it's the exports object. Since it doesn't really make sense to use
   this plugin in environments that don't have a window.navigator object,
   the code now just references 'window' directly.
2. The plugin did a global export if AMD wasn't detected, which assumed
   there was a global jQuery object. The added module.exports-detection
   uses require to pull in jQuery instead.

[le717]

Have you successfully tested this in AMD and Node/Browerify environments and ensured the tests still pass?

[mwiencek]

I've tested the changes in a project using browserify 7.0.1 and jQuery 1.11.2. The tests pass now after 4ad34a3.

require('jquery') won't work out-of-the-box with pre-1.11 jQuery, since they didn't have a main field in package.json, but I assume anyone using older jQuery versions with browserify already have some sort of shim setup for it. And this is still better than not working at all. :)

I don't have any AMD project/setup to test these changes with, but I assume it'll work identical to before because the typeof define === 'function' && define.amd is still the first branch and unchanged, so the only change in the code path for AMD environments should be where it references window directly in the source.

[le717]

I'd rather this written right after the comment at the top (line 15, with a blank line after it and before (function...).

[mwiencek]

I'd rather this written right after the comment at the top (line 15, with a blank line after it and before (function...).

Done so.

[le717]

Just that one minor nit and this should be fine.

[le717]

Thanks for the contribution!

[gabceb]

I've added simple RequireJs testing on 3f6c1da