[Propel] Added new method to return a query to use in findByIdentifiers().
[Propel] Added new method to return a query to use in
findByIdentifiers().

That way, it's easier to override the default ElasticaToModelTransformer
class.

peterkokot/FOSElasticaBundle,alekitto/FazlandElasticaBundle,fazland/FazlandElasticaBundle,ramuss/FazlandElasticaBundle,ramuss/FazlandElasticaBundle,alekitto/FazlandElasticaBundle,Exercise/FOQElasticaBundle,fazland/FazlandElasticaBundle