Add --repository-config option to set base branch for submodules

[rleigh-codelibre]

Testing:

• clone https://github.com/ome/bio-formats-build.git
• build and install scc
• run scc merge --repository-config=repos.yml master --no-ask --reset --update-gitmodules -D none -I user:rleigh-codelibre -v for example
• the configuration can be used recursively if submodules contain submodules (add a submodules section alongside base-branch in the submodule definition). The dict for the submodule will be passed to submodule GitRepository initialisation.

repos.yml example:

base-branch: master

submodules:
  ome-common-java:
    base-branch: master

  bioformats:
    base-branch: develop
    
  bio-formats-autogen:
    base-branch: master
    
  bio-formats-bundles:
    base-branch: master
    
  bio-formats-documentation:
    base-branch: master
    
  bio-formats-imagej:
    base-branch: master
    
  bio-formats-matlab:
    base-branch: master
    
  bio-formats-test:
    base-branch: master
    
  ome-codecs:
    base-branch: master
    
  ome-common-java:
    base-branch: master
    
  ome-jai:
    base-branch: master
    
  ome-mdbtools:
    base-branch: master
    
  ome-metakit:
    base-branch: master
    
  ome-model:
    base-branch: master
    
  ome-poi:
    base-branch: master
    
  ome-stubs:
    base-branch: master

[manics]

FYI there are some long-standing requests for scc and omego to support a config file to save having to define common args on the command line, e.g.

• Use ConfigArgParse omego#76
• Omego, webserver and config omego#39
• Use ConfigArgParse if available yaclifw#7

[rleigh-codelibre]

Presumably, once ome/yaclifw#7 is merged we could switch over to use it.

[manics]

I only mentioned it because of the naming of the new parameter --config which sounds quite generic.

[rleigh-codelibre]

Yes, it could be renamed to something more specific. Or, we could allow more than branch configuration in the future. For example, it could be extended to support per-repository filtering options etc.

[rleigh-codelibre]

Renamed --config to --repository-config. I used "repository" rather than "branch" because it's more related to repositories regarding submodules and base branches.

[sbesson]

The changes proposed here make sense, are overall backwards-compatible while allowing more granularity on the control of some of the filter options via a YML configuration file. The support for file-based flexible configuration is something that has been discussed as a more generic feature (see ome/yaclifw#7) and having such a concrete driver is a good first step.

Assuming the unit and integration tests pass, happy for this to be released as 0.9.0.

NB: as an extra feature, should I open a PR to port to scc the project-wide VERSION strategy implemented in omego in ome/omego#114. Depending on the timeline, this should be completely safe to be pushed to a follow-up patch release.