net/bandsnatch: update to 0.2.0

Breaking Change
- The previous behaviour of running the download job with the base command has
  been moved into its own subcommand run in order to accommodate some features
  I plan to add in the future.

Added
--dry-run flag to get a list of releases Bandsnatch would try to download,
without actually downloading them.
--debug flag to get some extra information in certain circumstances (Might be
changed to --verbose in the future if I change my mind).

Fixed
- Fix problem where some releases could crash a thread with missing field
  'download_type'.

Changed
- New run subcommand which replaces the previous functionality of running the
  downloader on the base command.

(pin)