We should provide means to discover connection factories so that clients can easily take a connection specification and then look up and configure the appropriate connection factory.

Using JDBC provides some convenience in terms of providing a connection URL and the infrastructure components figure out, which driver to use. We do not want to include URL parsing in R2DBC drivers yet we want to get a chance to retain convenience from a user's perspective to potentially reuse a JDBC URL and a client component should be able to determine the driver and configure the connection factory.