Add support for local repository

[iliapolo]

Currently the repository files are stored under ~/.dictconfig/. This is hardcoded and not configurable.

It is ok for interactive usage, but very bad for automation. Thinks of the following scenario:

1. CI cleans workspace and checks out repository
2. CI runs dictfile to modify a file in that repository
3. CI cleans workspace and checks out repository
4. CI runs dictfile to modify a file in that repository --> this will fail because dictfile will complain that its last committed version is different than the current one, so it will not agree to make changes. The failure is actually good because this feature helps preventing manual modifications to files.

We do however need to support running with a local repository, this way when the CI cleans the workspace, it will also remove the the .dictconfig directory and all will be good.