* libgimptool
	* libgimptool/.cvsignore
	* libgimptool/Makefile.am: a library that contains tool code shared
	between the core and plugins

	* app/tools/gimptool.h: Removed here ...

	* libgimptool/gimptool.h: ... and added here

	* libgimptool/gimptooltypes.h: various types used by the tools.
	GIMP_CHANNEL_OP_FOO must be declared before this file is included.

	* libgimptool/gimptool.c: parts of the implementation of the GimpTool
	class that are not specific to the core

	* libgimptool/gimptoolcontrol.h: new class that contains the state
	and control information of the tool. Only the .h file is here because
	the plug-in code is completely different from the core code.

	* libgimptool/gimptoolmodule.[ch]: the GTypePlugin that loads the tool
	plugin modules.  The registration code is not included here and must
	be supplied by the core or plug-in. Because registration in the core
	requires a Gimp object, but pluginspace has no Gimp (nor...