Estimate the size of the database

[bourque]

It would be useful for our work in creating the database schema (issue #6) if we had a rough idea of how big we think the database will eventually be. It may tell us if we need to be concerned about disk space and/or memory issues, which could dictate how we structure the schema.

[bourque]

It seems that we are going to be using the existing "science tables" database, so this question needs not to be answered anymore.