Margins gone from xfdesktop

[Jasper Huijsmans]

Hi all,

I just removed the margin settings from xfdesktop. There were some
issues with it yesterday and Olivier and I agreed the way margins are
handled now is not correct. So, the solution will be to make the margin
settings an option for xfwm4 (as it should have been all along, really).
Until this is implemented there will be no margins available. Sorry.

	Jasper

PS
I also added some mostly empty docs, to make it easier for someone to
start adding text and/or screenshots.