Coincidences

This is meant to add the processing of coincidences to the publicdb.
Daily ESD data will be analysed for coincidences, which will be stored in the ESD.
Histograms will be generated to give an overview of the coincidences.

Currently it is meant to use all stations in the network when looking for coincidences.
We could add the processing of coincidences for cluster, though that should just be a subset of the full network..

The coincidence module in SAPPHiRE does not seems to keep a nice reference to the original data entry,
it simply copies all events that are part of a coincidence to a new table.
This increases disk usage, perhaps we can make it work with nicer pointers back to the original tables.

To be added are views which show the histograms for the daily network-wide coincidences.