(call_debugger): Take full care of extending stack limits

(call_debugger): Take full care of extending stack limits
to make space for the debugger, and restore the change afterward.
Bind debug-on-error to nil.
(restore_stack_limits): New subroutine.
(Fsignal): Extend specpdl bound along with eval depth bound,
for calling edebug.  Don't do either one, for calling debugger.
(find_handler_clause): Don't bind debug-on-error here.
Don't unbind anything either.
Temporarily advance max_specpdl_size for calling
internal_with_output_to_temp_buffer.
(grow_specpdl): Don't alter max_specpdl_size before signaling an error.
(syms_of_eval) <max-specpdl-size>: Doc fix.