Convert FwdPtrProducer to stream Producer

Static analyzer and helgrind show it is safe to convert this class
to be a stream based Producer. Thread performance analysis showed
this conversion is needed for efficient threading.
Make GsfElectronBaseProducer a stream module.

Static analyzer and helgrind show it is safe to convert this class
and all classes inheriting from it to be a stream based Producer.
Thread performance analysis showed this conversion is needed for
efficient threading.
Convert ElectronIDExternalProducer to stream Producer

Static analyzer and helgrind show it is safe to convert this class
to be a stream based Producer. Thread performance analysis showed
this conversion is needed for efficient threading.
Merge pull request #4083 from Dr15Jones/makeFwdPtrProducerStreamModule

Convert FwdPtrProducer to stream Producer.
Merge pull request #4088 from Dr15Jones/makeElectronIDExternalProducerStreamModule

Convert ElectronIDExternalProducer to stream Producer
Merge pull request #4087 from Dr15Jones/makeGsfElectronBaseProducerStreamModule

Make GsfElectronBaseProducer a stream module.
Bring back behavior pre #4004.
Merge pull request #4105 from ktf/cleanup-4004

Cleanup #4004.
Merge remote branch 'origin/CMSSW_7_1_X' into CMSSW_7_0_X