#795 one routine to identify contiguous segments of data

[Jeremy Faden]

Every year or so we need to identify blocks of continuous data, and I've decided to add a routine to do this. identifyContinuousBlocks will take a set of timetags and a cadence limit and will identify continuous blocks of data. Also it allows the previous result to be passed back in, so that file-boundary-crossing contingous blocks will be properly counted as well.

[Jeremy Faden]

See https://github.com/autoplot/dev/blob/master/demos/2023/20230112/fromDatFiles.jy

[Jeremy Faden]

I found a few bugs associated with this rarely-used routine, see https://github.com/autoplot/dev/blob/master/demos/2023/20230112/demoNullPointerException.jy