Fix formatting of output strings to match pre-JSON values

The number conversion in the JSON output created some output
regression due to values for mag and probability no longer
being handled like strings.  These tweaks explicitly put out
the previously-expected values.
Add a default outdir to starcheck.config
Add Python source to SHA file calculation
Docstring and helptext updates
Fetch 3 weeks of telemetry (and match comment) instead of 7 days
Remove unused argument and imports