screenshot plugin and xfmenu grab

[Jani Monoses]

> I haven't looked at the code, but what is the advantage of making this a 
> plugin? I would think a screenshot utility that can be run from a 
> launcher will work just as well and it has the advantage of being able 
> to bind it to a shortcut.

Indeed, that would be nicer. I started from the existing plugin and 
while thinking it should eventually be an external plugin callable 
standalone I did not think of actually dropping the plugin capabilities.

One thing I see as and advantage for the plugin as that one could 
configure it instead of the launcher on right click, with no need for
separate config-file handling.
show-desktop and the action plugins are can also be done using small 
progs which could be separately bound to keys, I thought of the 
screenshot plugin along similar lines.

Jani