Improve handling gaps in mseed data

[mcshicks]

In addition to being delayed is appears there can be big gaps in mseed OOI data. From hackathon testing we noticed this pretty large gap in mseed data that put the conversion code in very long wait on startup.

pull_1 | filename: OO-HYVM2--YDH-2021-05-07T14:40:00.000000.mseed file delay: 1 day, 7:46:38.620951
pull_1 | filename: OO-HYVM2--YDH-2021-05-07T14:45:00.000000.mseed file delay: 1 day, 7:41:38.620951
pull_1 | filename: OO-HYVM2--YDH-2021-05-08T00:16:40.205688.mseed file delay: 22:09:58.415263
pull_1 | filename: OO-HYVM2--YDH-2021-05-08T00:20:00.000000.mseed file delay: 22:06:38.620951
pull_1 | filename: OO-HYVM2--YDH-2021-05-08T00:25:00.000000.mseed file delay: 22:01:38.620951