Fast MongoDB writer
Enable the MongoDB direct writer only in Mongo env
Fixes old names not refactored
Merge branch 'master' into direct_mongodb_writer

Conflicts:
	src/Pim/Bundle/BaseConnectorBundle/Resources/config/storage_driver/doctrine/mongodb-odm.yml
Perf optimization on unique value check
This optim provides a x4 perf improvement on a 100.000 lines import
Switch to product to array conversion and add update
Always update the "updated" date
Better management of multiple options
Fix date problem
Add normalization of association
Add MongoDB specific normalizers configuration
Upgraded BatchBundle to dev branch
Added upgrade documentation
Fixed spec
Adding specs for normalizers
Spec for Metric normalizer and bug fix
Spec on ProductNormalizer
Spec for ProductValueNormalizer
Configuration for MongoFactory injection
New service to massively insert pending versions