* gdbtk.tcl (create_file_win): Eliminate text widget B1 binding so

	* gdbtk.tcl (create_file_win): Eliminate text widget B1 binding so
	double-clicking will work again.
	(create_asm_win): Put "break" at end of all B1 bindings.
	(create_file_win): Lower "sel" tag, don't raise it.
	(ensure_line_visible): New proc.
	(update_listing, update_assembly): Use it.
	(create_copyright_window): Destroy window on Leave event.
	(create_command_window): Put "break" at end of all B2 bindings.