Add partitioning

[tmaiaroto]

Add partitioning options for Postgres via a trigger. Probably use: https://github.com/keithf4/pg_partman

Though I was trying to add code to create partitions on cron jobs within Social Harvest (and did). I'd have to expand on it though. This manager repository seems to have some functions all ready to go that would work well for Social Harvest's needs. Might need modification on date ranges though.