Add --describe and --describe-file options to remote mode.
Add --describe and --describe-file options to remote mode.

Plugin mode can just uobjects.localSlotNames.

	* src/libuobject/main.cc (main): --describe print the list
	of UObjects and exit, --describe-file FILE write said list
	to a file.

aldebaran/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi