Show changes

Allow to show what are the changes on the API (specially the ones that break it) so it could be decided if they could be resorted to several version-based branches, it's said, maybe some changes could be moved to a different branch and delayed for a future bigger version with other several breaking API changes. Instead of use just a counter, it could be implemented by using an array and pushing on it the changes found and using the `length` property.

Start by locating the existing API-diffing logic and the counter that tracks changes. Review how changes are detected, then define how individual changes and breaking changes should be exposed so version-based branch decisions are possible; done means the API reports those changes rather than only a total.

Written by the indexing model from the issue text.