repolist command missing default for option format -> Exception

[e3krisztian]

Missing default makes the --format option mandatory:

$ homely repolist
Traceback (most recent call last):
  File "/home/???/.local/bin/homely", line 11, in <module>
    sys.exit(main())
  File "/home/???/.local/lib/python3.6/site-packages/homely/_cli.py", line 346, in main
    homely()
  File "/home/???/.local/lib/python3.6/site-packages/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/home/???/.local/lib/python3.6/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/???/.local/lib/python3.6/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/???/.local/lib/python3.6/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/???/.local/lib/python3.6/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/???/.local/lib/python3.6/site-packages/homely/_cli.py", line 37, in proxy
    command(**kwargs)
  File "/home/???/.local/lib/python3.6/site-packages/homely/_cli.py", line 140, in repolist
    print(format % vars_)
TypeError: unsupported operand type(s) for %: 'NoneType' and 'dict'