2006-09-12  Michael Natterer  <mitch@gimp.org>

	Added new tool API for modifier key events while the tool
	is active and implement it in the rect select and crop tools.
	Fixes bug #316156 and bug #355302.

	* app/tools/gimptool.[ch]: added GimpTool::active_modifier_key()
	and public function gimp_tool_set_active_motifier_state(). Remember
	the active_state at button_press and reset it on button_release.
	Ignore releases of modifiers that were pressed at button_press (but
	only ignore them once).

	* app/tools/tool_manager.[ch]: added wrapper
	tool_manager_active_modifier_state_active().

	* app/display/gimpdisplayshell-callbacks.c
	(gimp_display_shell_events): return FALSE for all modifiers even
	when mouse button 1 is pressed.

	(gimp_display_shell_canvas_tool_events): when bouse button 1 is
	pressed *and* the tool is active, dispatch the new active_modifier
	events to tools.

	* app/tools/gimpcroptool.c
	* app/tools/gimprectangleselecttool.c
	* app/tools/gimprectangletool.[ch]: implement active_modifier_key()
	instead of modifier_key().