* gdbtk.tcl (add_breakpoint_frame): Add more fields.
* (create_file_win create_asm_win build_framework): Create null
bindings for meta keys to keep window from dropping down to
insertion point when meta is pressed by itself. New bindings:
Up/Down - Scroll up/down one line at a time
Next/Prior - Scroll up/down one page at a time
Home/End - Warp to current pc/end of file
* (build_framework): Turn on breakpoint menu.
* (create_command_window): Implement tab completion. Add binding
for ^C to stop target.