Add preference for showing exact or relative dates.
Make the showWhitespaceDifferences preference work.
Make the context slider in the diff views work.
This is done with a minimal version of jQuery 1.3.2 being responsible for the animation and
a small cookie storing the last value between page refreshes so that it can be incremented by the HTML sliders
default value.
TODO: Maybe we can also make the default context value into a preference?
Store all the open documents when the app closes and then open them when the app starts again. Defaults to NO, so that there is no change to the existing behavior.
We don't want to do this in the commit view, as that way you can't
commit whitespace differences. You'll never be able to have a clean
working tree, and you can't see why the files remain 'unstaged'. So, we do this
only for the history view :)