RFC: Get rid off third-party storage requirements

[AndrewDryga]

Right now we have a PostgreSQL infrastructure requirement, but it looks like an overkill for a simple configuration storage. Instead, we could leverage something far simpler and built into Erlang (eg. Mnesia or DETS.)

Arrising question: how to sync data between instances?..

[LucasBadico]

Well, for me have a database is a needed evil, but I'm really think on make use of dynamodb, so a option, instead of get rid off is to give the option to choose the database, adapter and stuffs.