Working Rotate Gesture Pull

[sashadev-sky]

Fixes #165 (<=== Add issue number here)

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pending:

• use new rotation property tracking (added in #275) to debug a problem where image "stops rotating and bounces back"

• update PR so that it has both the implementation using Hammer.js and no library if can't decide which one is better

• clean up code / implementation. add to my demo page so jywarren can test easily.

• Need to add a panTo so that if you try to rotate an image that is off screen a little bit, the screen will move so its not anymore or an error will be thrown.

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[sashadev-sky]

@jywarren this is now working. Needs a lot of cleaning.. shouldn't all be inside of the load event of course and for testing purposes map moving is disabled. Need to add a panTo so that if you try to rotate an image that is off screen a little bit, the screen will move so its not anymore or an error will be thrown. The question is how would you like this to be implemented?

Is this for touch screens only? currently it works on both (click or touch and drag). Note there needs to be some sort of logic to separate moving the image from rotating it.