Remove pre-content-sync cordova.js files

[filmaj]

The following is no longer needed:

• res/middleware/cordova
• res/middleware/hammer
• lib/middleware/cordova
• doublecheck lib/middleware/ext/session regarding device version/platform tracking, as that may be purely needed for old cordova stuff.

[filmaj]

@timkim @surajpindoria can either of you confirm we are safe to remove both:

1. res/middleware/cordova stuff
2. res/middleware/hammer stuff

I also love how the one bit that actually does anything with hammer is a test that checks that we don't include hammer 😆

[timkim]

I think you are safe to remove both. I'm trying to remember what we used hammer.js for... I think it was for windows stuff.

[surajpindoria]

Hammer was the old way of handling the touch events, 3/4 finger taps. I believe it was Windows