adding wlhe2HepMCConverter_cff.py
removed tinyxml and point to the one in FWCore
Merge pull request #840 from lenzip/53X-fixTinyXmlForRivet

removed tinyxml and point to the one in FWCore
Merge pull request #766 from inugent/wlhe2HepMCConverter53xb

adding wlhe2HepMCConverter_cff.py