The original decision to avoid index.html was because it only works with a build step. Since we've all accepted a build step, the more sensible name is index.html. Without this change, every hosted example has a link to http://openlayers.github.com/ol3/master/examples/example-list.html which 404s.
This commit adds several features:
- rename of class to better reflect its behaviour
- full ol.Object support
- integration with postrender event for integration with animations and
render loop
- minimised DOM modifications
- more precise positioning
- element placed in DIV to avoid modifications to user-supplied element
- correctly handle changes to the positioning property
