DATAJPA-564 - Allow SpEL expressions to be the only consumer of query method parameters.

We now allow the parameters of query methods to also be exclusively consumed by expressions within a given query string. Previously this wasn't possible due to to strict checks for parameter usage in JpaQueryMethod.
Relax check for query param usage in JpaQueryMethod.
Enabled HSQLDB support for oracle syntax to be able to use the ROWNUM() function for pagination.