TypeError when using the old config file format

[holmboe]

After #59 was merged we get this error when using the old config file format.

❯ subgit pull
Exception type : TypeError
EXCEPTION MESSAGE: string indices must be integers
To get more detailed exception set environment variable 'DEBUG=1'
To PDB debug set environment variable 'PDB=1'

Here is the traceback:

Traceback (most recent call last):
  [...]
  File "/home/nn/code/github.com/dynamist/subgit/subgit/core.py", line 354, in pull
    active_repos = self._get_active_repos(config)
  File "/home/nn/code/github.com/dynamist/subgit/subgit/core.py", line 335, in _get_active_repos
    repo_name = repo_data["name"]
TypeError: string indices must be integers

[holmboe]

We should probably cut a new release quite soon.

Another reflection on this: could we handle change to the config file format better going forward? Add a version identifier? Each semver major version of subgit would expect only non-backwards compatible changes?