fatbuildrctl patches crash with unmatched checksum

[rezib]

For example :

$ fatbuildrctl patches -a fatbuildr -b pkgs
Traceback (most recent call last):
  File "/usr/bin/fatbuildrctl", line 33, in <module>
    sys.exit(load_entry_point('Fatbuildr==2.0.1.dev45', 'console_scripts', 'fatbuildrctl')())
  File "/usr/lib/python3/dist-packages/fatbuildr/cli/__init__.py", line 34, in run
    cls()
  File "/usr/lib/python3/dist-packages/fatbuildr/cli/fatbuildrctl.py", line 437, in __init__
    args.func(args)
  File "/usr/lib/python3/dist-packages/fatbuildr/cli/fatbuildrctl.py", line 1060, in _run_patches
    patch_queue.run()
  File "/usr/lib/python3/dist-packages/fatbuildr/patches.py", line 97, in run
    source.id, self._dl_tarball(source)
  File "/usr/lib/python3/dist-packages/fatbuildr/patches.py", line 159, in _dl_tarball
    verify_checksum(
  File "/usr/lib/python3/dist-packages/fatbuildr/utils.py", line 77, in verify_checksum
    raise RuntimeError(
RuntimeError: sha256 checksum do not match: 3fc4df609620ef55bce84aaa262a7009fe7da70a2a8dff146d7b814cae566194 != 7160a42880e3b25d6edc5998b19cc00da13697cac14fc302ac05013dd52ec596

In this case, fatbuildrctl should report the error nicely.