add danger-js or native equivalent

[woeps]

Add danger-js or some native equivalent to this repository to validate pull requests and automatically comment on them with warnings / errors.
E.g.: if changelog was not modified

If you know some alternative for native, please comment!

[woeps]

Another approach could be to use Rely.
Custom Matcher could implement similar rules to danger. E.g. check for modified files or for pr message content
A Custom Reporter could post a comment to the pr according to failed tests.

To evaluate: pros/cons using rely vs greenfield

[woeps]

Crazy idea: maybe this could be accomplished by Refabricator itself like:

• Fabricators.gitModifiedFiles to generate a list of modified files
• Refabricators.validateChangelog to validate the previously generated fabric(s): checkbif changelog is in the list
• Factories.gitHubCommentPr to comment on github pr with errors