Optionally return dockbar to initial position

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Having put the dockbar shortcuts in order of relevance, I would find it useful 
if the bar could be optionally reset to initial position every time that home 
is pressed. This way we could always have the most useful icons at hand and 
would always instinctively know where to search them.
Consider to offer initial position at left or right, as many right handed 
people could find easier to click the right part of the screen, even if this 
would mean a reversed order.

Original issue reported on code.google.com by giulio.m...@gmail.com on 13 Dec 2010 at 9:03