Allow for any characteristic that is not read-only, which should leave out all string characteristics.
Upon reset, zero out all 8 bytes of UVal memory, instead of simply setting UVal.BOOL to false. This allows use of TimedReset for any characteristic with a numerical value.
Updated SpanRange to register itself automatically to the most recent Characteristic. This is more consistent with the overall framework and no longer requires user to access the range variable directly.