Mseed file overwrite on day of cf-card swap

When two cf cards are used at a given station (common situation), rt2ms will process the data on the two cf cards separately and generate a daylong mseed file for each day and each datastream.

On the day the cf cards are swapped, rt2ms will process the data packets before the swap and output a mseed file, and then process the data packets after the swap and output a mseed file. The two outputted mseed files share the same name and are saved under the same directory structure leading the second file to overwrite the first.

See rt2ms.msg for more details on the issue.