Move away from using rfam database

[ivasio]

Goals:

1. allow our users to easily run example sql database sources on an interesting and real dataset, without any upfront setup
2. use it internally to test mysql as a data source, rfam has plenty of indexes and foregin references + some pretty big tables

Requirements

• bring up an mysql instance with a restored dump
• allow for read only, no ssl access (ssl setup is PITA for mysql and we want to make it easy for our users)
• pick one of our cloud providers for managed service. you may encounter a problem with mandatory SSL. we can also go for digital ocean
• you may consider a server instance where some tables trimmed so we are not overloaded with huge queries

Tasks

1. • update all our docs and code with new rfam connections string
2. • enable all rfam tests hidden under rfam marker