Fix reference to TimedItem

As reported:
http://lists.w3.org/Archives/Public/public-fx/2014OctDec/0056.html
Fix description of reverse()

As reported:
http://lists.w3.org/Archives/Public/public-fx/2014OctDec/0058.html
Fix pausing procedure

Based on:
http://lists.w3.org/Archives/Public/public-fx/2014OctDec/0050.html