Add RefToBase member `holder_' as transient in Reflex dicts.

RefToBase is a templated class with a private memeber holder_ of
reftobase::BaseHolder<value_type>* type. The following type is
not part of any dictionary, thus holder_ is not saved.

Example error generated by ROOT:

Error in <TStreamerInfo::Build:>: edm::RefToBase<reco::Electron>:
edm::reftobase::BaseHolder<reco::Electron>* has no streamer or
dictionary, data member holder_ will not be saved

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
fixes to CMS_EWK_11_021
Add edm::reftobase::BaseHolder<*> type into a dictionary.

The following is needed for edm::RefToBase<*>, to store holder_
data member.

From Dr15Jones:
  holder_ must be stored since it holds all the information we need
  to retrieve the data. BaseHolder is an abstract base class but its
  concrete implementations ultimately hold an edm::Ref which must be
  stored

Signed-off-by: David Abdurachmanov <David.Abdurachmanov@cern.ch>
Keep orphan particles - this gives consistent result with original HepMC
compile error
EfficiencyVsTrueSeparation
EfficiencyVsTrueSeparation
EfficiencyVsTrueSeparation
Modified catch statement to edm::Exception
fixes to reference plots to have axis limits consistent with the paper
Make getObj in the *Generator classes thread safe by not returning pointer to member data obj_.
Each module is assigned its own unique ID which is accessible via its edm::ModuleDescription. The id is assigned in a thread safe manner.
From normal vectors to const &
From normal vectors to const &
Add function to calculate ID of empty parameter set without registering it
Unit test extension for context classes

Extend existing unit tests to cover the
content of the context classes as they are
passed to the services in the callback
functions.
Merge pull request #280 from wmtan/calculateIDofEmptyParameterSet

Add function to calculate ID of empty parameter set without registering ...
initial commit
cleanup
Switch to LogInfo when GEM geometry is missing. It's valid for current detector.