* app/tools/gimpnewrectselecttool.[ch]: new rectangle select tool

	* app/tools/Makefile.am
	* app/tools/gimp-tools.c: add it to toolbox

	* app/tools/gimpselectionoptions.[ch]: set its options

	* themes/Default/images/tools/stock-tool-new-rect-select-16.png
	* themes/Default/images/tools/stock-tool-new-rect-select-22.png: toolbox
	icon

	* libgimpwidgets/gimpstock.[ch]
	* themes/Default/images/Makefile.am: add the toolbox icon