Add to JDBC module ability to set up a testing H2 database with the specific dialect

[zaleslaw]

The existing API proposes a strict and not flexible approach to defining the type of the database via parsing URL in DatabaseConfiguration, it makes impossible to use H2 for the testing capabilities

It also related to the task making the approach of new source registration possible via the API

The solving of this task highly likely involves the documentation changes for KDF library and the full Kotlin site