Fix for #1214, #1216, #1234 (problem with animations). In a nutshell, the callback needs to occur even if the animation does not run.

Removed useless safari workarounds, added rerun-single-test feature: just doubleclick on a single test to execute that one, use browser's back button get back to executing all

unique() for speed improvement reasons. Document this fact and also be
clear about the fact that merge() is a generic function while unique()
really works just with jQuery objects.

improve documentation of animate() function by mentioning both the 'swing' and 'linear' easings which are provided by default

Added support for the event object properties relatedTarget, metaKey, which, and charCode. Fixes bug #1204.