raise all pre-commit errors to user

[Ivar Lazzaro]

Driver managers use the raise_orig_exc flag to determine whether a specific exception should be raised as is to the user or wrapped into a generic 500 error.

As of today, the only 2 methods that use the reraise mechanism are create_port_chain_precommit and create_flow_classifier_precommit. I think we should extend this to all the precommit driver methods for better debugability of driver validation errors.