Use specific YAML keys instead of "name" in repo-config.yaml

The current repo-config.yaml style looks like this:

configurations:

• name: base

  projects:

  - name: project1

    modules:

    - name: module1

  - name: project2

    modules:

    - name: module2

In a long file, the indentation alone is not a very strong visual clue to find the line where a new project starts. I suggest a change to this format:

configurations:

• configuration: base

  projects:

  - project: project1

    modules:

    - module: module1

  - project: project2

    modules:

    - module: module2