Add robomatch recommendation feature

[vrortvedt]

I recommend the creation of a robomatch feature, which would work similar to a sent match recommendation except that it would have no sender.

Standard implementation of this feature would utilize the affinities selected by each user, and for those users who had selected at least 3 affinities, identify the most closely matched pairs among non-connected members. Perhaps a bitwise operation would work for this.

The robomatch would occur a single time during a Gathering, perhaps at the halfway mark between creation and expiration. Matched users would each receive a notification at the connect button and would see that he or she had a robomatch recommendation based on shared affinities. Connecting with one's robomatch would result in an award of three points.

Perhaps a note could be added to the downloadable contact info indicating that a connection was the result of a robomatch.