Reconsider unique columns in e.g. mcsData

We have non-null serial columns in many databases (e.g. mcsData has mysid) which are probably not needed – the natural join key is usually (frameId, fiberId) and we should probably that tuple be the unique constraint and primary key (cf. this stack overflow answer)

This will save a little space, and should also speed up access significantly. In some cases the moveId will need to be included too.

In the cases that we do need a serial column, I propose that we always name them tableNameId (e.g. mcsDataId), or possibly mcsDataSerial to reduce confusion with e.g. fiberId