OAK-1533 - RdbDocumentStore should use a connection pool

Making dbcp as optional as its not required for default setups

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1578787 13f79535-47bb-0310-9956-ffa450edef68
OAK-1533 - RdbDocumentStore should use a connection pool

Adding a test scoped dependency on dbcp as dbcp dependency is optional in oak-core

git-svn-id: https://svn.apache.org/repos/asf/jackrabbit/oak/trunk@1578788 13f79535-47bb-0310-9956-ffa450edef68