postgresql/cockroachdb: Add generic JSONB types

[maxbrunet]

Hello there! 👋

This adds the generic types JSONMapOf[T] and JSONBArrayOf[T] to the postgresql and coackroachdb adapters while maintaining backward compatibility.

I have aliased the JSONBMap and JSONArray and marked them as deprecated, these names could easily be re-used if/when breaking changes are acceptable.

I took the opportunity to review and update all the links and references in the doc comments of these 2 modules