Update to include transactions and more up to date Postgres connection management

...ibility, and  a function for calling stored procedures. I also changed the way Dorm interacts with the postgres module. I removed it's interaction with connection pools and set it up so it only uses one client and one connection. This provides better support and functionality for using transactions. It probably hinders it's ability to utilize concurrent transactions though, so it will probably need to be modified in the future. Possibly using a special transaction object or something like that.