Add version subcommand

[hugovk]

Make it easier to find the version by adding common options.

Before

❯ blurb --version
Error: Unknown subcommand: --version
Run 'blurb help' for help.

❯ blurb -v
Error: Unknown subcommand: -v
Run 'blurb help' for help.

❯ blurb version
Error: Unknown subcommand: version
Run 'blurb help' for help.

❯ blurb help
blurb version 1.2.2.dev8

Management tool for CPython Misc/NEWS and Misc/NEWS.d entries.

Usage:
    blurb [subcommand] [options...]

Available subcommands:

  add        Add a blurb (a Misc/NEWS.d/next entry) to the current CPython repo.
  export     Removes blurb data files, for building release tarballs/installers.
  help       Print help for subcommands.
  merge      Merge all blurbs together into a single Misc/NEWS file.
  populate   Creates and populates the Misc/NEWS.d directory tree.
  release    Move all new blurbs to a single blurb file for the release.
  test       Run unit tests.  Only works inside source repo, not when installed.

If blurb is run without any arguments, this is equivalent to 'blurb add'.

After

❯ blurb --version
blurb version 1.2.2.dev8

❯ blurb -v
blurb version 1.2.2.dev8

❯ blurb version
blurb version 1.2.2.dev8

[ezio-melotti]

Codecov says the print is not covered by tests despite the line you added in the tox.ini. Should a simple test ran through pytest be added too?

[hugovk]

Codecov says the print is not covered by tests despite the line you added in the tox.ini. Should a simple test ran through pytest be added too?

Yes, we only have coverage through pytest. Sure, I can add a simple test case.

[ezio-melotti]

Thanks!