Add a --custom mode to urbi-launch to force the core-dll location.
Add a --custom mode to urbi-launch to force the core-dll location.

Required for testing without installing.

	* src/urbi-launch: Document and implement --custom option.

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