DATAMONGO-633 - Upgraded to Querydsl APT plugin 1.0.8.
DATAMONGO-636 - Added support for countBy in derived queries.

We now change the query execution to a count execution in case a derived query has the PartTree.isCountProjection() set to true or a query defined in @Query has the newly introduced count() attribute set to true.

As the native Mongo count() returns a long we use a default ConversionService to potentially massage the query result into other numerical types.