use Hibernate's short-name strategy mechanism to avoid exposing implementation details

[NathanQingyangXu]

Hibernate has a Stragety mechanism (a little misleading for it refers to 'short-name' service, instead of Stragety Pattern) as examplified in Hibernate Integration Guide(https://docs.jboss.org/hibernate/orm/6.6/integrationguide/html_single/Hibernate_Integration_Guide.html) . As the doc explains:

Think of this as the short naming service. Historically to configure Hibernate users would often need to give fully-qualified name references to internal Hibernate classes. Of course, this has caused lots of problems as we refactor internal code and move these classes around into different package structures. Enter the concept of short-naming, using a well defined and well known short name for the strategy/implementation class.

It might be a good feature to our product with similar concern. The customization is based on the common ServiceLoader mechanism Hibernate mainly depends on (as an example stragety registration implementation in the doc).

A similar PR used to be created previously: #34. This PR is a new one based on the latest codebase.

HIBERNATE-124

[stIncMale]

Thank you, @NathanQingyangXu. I created HIBERNATE-124: Introduce short names for MongoDialect/MongoConnectionProvider, rename com.mongodb.hibernate.dialect/com.mongodb.hibernate.jdbc to com.mongodb.hibernate.internal.dialect/com.mongodb.hibernate.internal.jdbc
.