Two main changes in the regex:
* Ignore double quotes around interval numbers.
* Ignore second set of values (i.e. the one after the comma), as it
may not even be given).
We now support at least these two formats:
^SCFG: "Radio/Band",("1-511","0-1")
^SCFG: "Radio/Band\",("1"-"147")
Reported-by: Colin Helliwell <colin.helliwell@ln-systems.com>