Postgres LogStorage

Notes and Caveats

The current LogStorage part of the Postgres implementation was based off what was already written for MySQL. Thus, the two user-defined functions included in storage.sql. MySQL doesn't kill a transaction when a duplicate is detected, but PostgreSQL does. So, to preserve the workflow, I included the two functions which trap this error and allow the code to continue executing. The only other change I made was to fully translate the MySQL queries to PostgreSQL compatible ones and tidy up some of the extant tree storage code.