* gdbtk.c: New tcl commands: gdb_fetch_registers,

	gdb_changed_register_list, and gdb_regnames.
	* gdbtk.tcl:  Use monochrome color model for now.
	* (delete_breakpoint_tag create_file_win):  Add breakdot support.
	* (create_file_win create_asm_win update_listing build_framework
	create_source_window create_command_window):  Re-org window
	creation to give all windows consistent look and feel.
	* (update_listing update_asm):  Change pc pointer to '->'.
	* (registers_command reg_config_menu create_registers_window
	populate_reg_window update_registers):  Revamp register window.
	Allow selection of registers to be displayed.  Highlight changed
	registers.