[BUGFIX] Fixes repeating animation issue in IE 11 and below

See: https://github.com/miguel-perez/jquery.smoothState.js/issues/26

Next try ... This one has one problem but works good so far. $element ist forced to height: auto;. Any suggestions?

I have tested IE 11,10,9,8, Chrome 36 and FF 31 on Win 8.1.
I cannot see any problems with it, please test it as well.
Merge pull request #30 from geldmacher/patch-2

[BUGFIX] Fixes repeating animation issue in IE 11 and below