Explore new database options

[Varunram]

Since inception, we have stuck to boltdb simply because it is easy to add and delete new values as and when needed. But as the system matures, we need to think of a database architecture that is scalable and that which can support the needs of the frontend platform better than boltdb does right now.

Preliminary investigations of popular projects suggest postgres is a good option but we can explore other noSQL dbs like Mongo to see what advantages and disadvantages they have for the uses we desire.

This issues should ideally be done in conjunction with #97 so that the frontend can transition to the new solution better. This is also a huge undertaking that can take several weeks due to the complexity of the database solution and how it works with respect to openx (which would ideally still be using boltdb since there aren't a whole lot of fields that the user struct possesses)