Polyfill the bottom and right cases

[dvorapa]

Please polyfill the bottom and right positions. According to the actual version of the spec (http://dev.w3.org/csswg/css-position-3/#sticky-positioning), there should work all top,left,bottom and right css rules for positioning and each of them (unfortunately) behaves in its own way.

[matthewp]

Thanks @dvorapa! Unfortunately I don't have time at present to work on this project, but would be more than happy to take any pull requests (or add contributors who are able to work).

[dvorapa]

Thanks @matthewp for your reaction! Unfortunately I don't have any time to help.