enable/disable_breakpoint_hook with modify_breakpoint_hook.
* gdbtk.c: General cleanups, get rid of unused variables. Redo
handling of stdout/stderr to just return output as the result of
the tcl command that caused the output. Cleanup -Wall stuff.
* (breakpoint_notify): Now returns just action and breakpoint
number.
* (gdb_get_breakpoint_list): New routine. Does the obvious.
* (gdb_get_breakpoint_info): Mostly derived from the old
breakpoint_notify, but returns lots more info.
* (dsprintf_append_element): Helper routine, works like printf,
but appends a tcl element onto the specified DString. Good for
building up lists as return values.
* (gdbtk_enable/disable_breakpoint): Go away. Replaced with
gdbtk_modify_breakpoint.
* (*many routines*): Use new result protocol.
* (call_wrapper): Make sure that recursive calls don't trash results.
* gdbtk.tcl: New windows, autocmd, and breakpoints.
* (gdbtk_tcl_fputs): Don't use $current_output_win redirection
anymore. It's not needed (in fact, this routine may not be needed
anymore).
* (gdbtk_tcl_breakpoint): Change to reflect new breakpoint
notification protocol.
* (gdbtk_tcl_busy gdbtk_tcl_idle): Straighten out buttons, remove
catches.
* (interactive_cmd): Use this wrapper around button invocations
of many commands. This will catch errors and put the results into
the command window. It also updates all the other windows.
* Also, change reliefs of most things to sunken. This actually
looks better.
* (create_file_win): Fix margin binding to allow breakpoints to
work again.
* (create_asm_win): Use return value of gdb_disassemble instead
of implicit I/O to the command window.
* (create_command_window): Use new result protocol to get output
from commands.
* breakpoint.c (delete_breakpoint, enable_breakpoint,
disable_breakpoint): Don't call breakpoints_changed; it is now
called via the *_breakpoint_hook functions.
* annotate.c (_initialize_annotate, breakpoint_changed): New functions.
fputs_unfiltered and exit directly, rather than fatal. The latter
calls vfprintf_unfiltered!
* gdbtypes.h, gdbtypes.c (can_dereference): New function.
* value.h, printcmd.c (print_value_flags): Move from here...
* annotate.c: ...to here, and make it use can_dereference.
