How to setup dev environment for testing code fixes?

[gclough]

Could you please add some documentation on how to setup the dev/test environment? Do I need a locally running PostgreSQL database and two pgBouncer instances? What users/databases are needed?

I can probably figure it out by reverse engineering the tests, but if there's already a scripts or some docker containers with this already done then I I would appreciate it.

[gclough]

@maartenberg, @FaHeymann, you've done the most recent work... so any tips?

@jgduarte-stratio , @esanchezm , can we help you maintain this?