Correct time resolution for radar, and a few other items.

[stevechesley]

Four items here:

• Fixed mpc80coltoxml to round radar times to integer seconds. For optical, round to 0.01 sec if date has 1e-6 precision, to 0.1 sec for 1e-5 day precision and integer sec for lower precisions. Most of the action here is in sexDateToISO() in sexVals.py.
• Modified xmltopsv to copy the XML version into PSV. Prior version always wrote '2017' for version.
• Updated radar examples in ./tests/radar
• Rolled back from v2022a to 2022 in documentation. (Just added strikethrough in change log... Did not update file dates in file and filename...)

The new transformation of times from decimal date to sexagesimal time in sexDateToISO() is fairly well tested. I wrote a script to check all possible fractional day values and found no issues with times like 03:60:60, etc...

@federicaspoto It looks like the changes you are making to mpc80coltoxml on your fix_python branch are compatible with this pull request.

[federicaspoto]

@stevechesley looks good to me! Feel free to merge the branch. I'll pull everything in our local copy.