First stable release

Changes focus on polishing logs and the default behavior:
* Feeds that can be neither fetched nor parsed are now skipped
  instead of triggering an abortion the whole process.
  The old behavior can be toggled via the --strict option.
* URLs to the feed relevant to all errors/warnings
  should now be logged to stderr.
* Source code locations have been removed
  from user-facing warnings for concision.
-----BEGIN PGP SIGNATURE-----

iHUEABYKAB0WIQSDiv4NVdwHTjYPlDqEtpzm8/a3ZwUCZZ3TYAAKCRCEtpzm8/a3
Z4QqAQDwirNx+CtyOjLSy8tGM9yBrCgCOwkRN7+5L0oTn4qbLwEA+pGvSCFcQv+A
tMBm2YU7UBsImWHJR1vcoSN9FlcCkAQ=
=6KfP
-----END PGP SIGNATURE-----