OrbitDB Validation and Index updates

[fazo96]

@kulpreet the PR is marked as WIP because it's not finished, but I am trying to avoid breaking it so it can be reviewed and works in its current state

PR Content, in high level:

• better support for different OrbitDB Indexes
• added a NOOP Index that does nothing, we can use this in the wallet to lighten the load on the frontend while we do reads through the API Client
• IPFS Read operations now have a default timeout of 10 seconds. This default is configurable and also each call can have a specific different timeout. Fixes #48
• OrbitDB Abstract Index now runs validations before calling implementation specific write methods. This means the ChluDB API has changed and OrbitDB now has access to DID and Review Record contents! Fixes #96
• First implementation of the SQL Index (on Sqlite)
• added support for PostgreSQL and tests
• SQL Database: reading a review also returns latest version data, not only data for the specific version asked. This will help with the Query Server
• replace validation cache with OrbitDB Index, will make reads superfast if the data is known to be valid
• made integration tests pass, fixed bugs

What I'd like to do next:

• benchmarks
• Indexes in the SQL database
• remove pubsub chatter, instead use OrbitDB updates to detect new content
• API Servers: CLI option to use postgresql
• Query API Server: read directly from postgresql for getDID and readReviewRecord.

[fazo96]

@kulpreet I think this is a good point for you to review, I made fixes to other projects using ChluIPFS and tried them all in the integration tests and they pass (in fact you can see my last commits are all bug fixes :+1: )