Implement more refined concindence checking

[dtreffenstaedt]

A more advanced way to calculate coincidences and to resolve coincidence conflicts is in order.

Currently conflicting coincidences need to be kept together due to there not being a way to resolve those conflicts.

A possible way how to resolve them could be to score each partial coincidence and selecting only the highest scoring pairs as part of the coincidence.

Ultimately though there is always a potential for remaining conflicts due to incomplete datasets and each coincidence needs to be manually inspected.