We also document how the grpc test mode works, and why it currently
lacks coverage.
Changelog-Changed: pyln-testing: The grpc dependencies are now optional.
Mostly comments and docs: some places are actually paths, which
I have avoided changing. We may migrate them slowly, particularly
when they're user-visible.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
We'll rewrite the tests to use this infrastructure in the next commit.
Changelog-Added: The new `pyln-testing` package now contains the testing infrastructure so it can be reused to test against c-lighting in external projects
