NewNodeMetadata -> MakeNodeMetadata. It doesn't return a pointer, so
Make is more idiomatic.
Invoke MakeNodeMetadata when necessary. The zero value for a
NodeMetadata is no longer valid.
Split MakeNodeMetadata to two constructors. MakeNodeMetadata when you
don't have anything to prepopulate; MakeNodeMetadataWith when you do.
Also, a fix to the tests in app. We unmarshal a RenderableNode struct,
which has a JSON-ignored NodeMetadata field. The zero value is invalid,
so we need to fix that before performing comparisons.
- Move docker probe code into it's own module
- Put PIDTree behind and interface for mocking
- Disaggregate dockerTagger into a registry, tagger and reporter
- Similarly disaggregate tests
- Add mocks for docker container and registry
- Add test for docker events & stats
