DbInfoCode upgrade 3.1.0: multiple datasets with dropdown choice

I must confess that the postgresql integration is not yet there, made a start though, help welcome.
Multiple dataset with drop-down box seems to work somewhat, might need bugfixes.
What works for me is that I can switch between two datasets on my laptop (both locahost, one is mysql other is postgresql - but see note above on the use).
Purpose of this change is switching is between development on localhost an production on remote host.
All settings kept in regular gambas settings file.