add javadoc to RepoProvider

[todo]

Enki/core/src/main/java/com/github/stcarolas/enki/core/RepoProvider.java

Lines 6 to 9 in 642a9bc

	// TODO add javadoc to RepoProvider
	public interface RepoProvider<T extends Repo> {
	Seq<T> repositories();
	Option<T> download(T repo);

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This issue was generated by todo based on a TODO comment in 642a9bc. It's been assigned to @stCarolas because they committed the code.