Add a draw class for the CORRFW (produces a warning, will be fixed

Add a draw class for the CORRFW (produces a warning, will be fixed
later). Also, some bugfixes.

-This line, and those below, will be ignored--

M    PWG3/dielectron/AliDielectron.cxx
M    PWG3/dielectron/AliDielectronPair.h
M    PWG3/dielectron/AliAnalysisTaskMultiDielectron.cxx
M    PWG3/dielectron/AliDielectronVarManager.cxx
M    PWG3/dielectron/AliDielectronMC.h
M    PWG3/dielectron/AliDielectronCF.cxx
A    PWG3/dielectron/AliDielectronCFdraw.h
M    PWG3/dielectron/AliAnalysisTaskDielectronSE.cxx
M    PWG3/dielectron/AliDielectronMC.cxx
M    PWG3/dielectron/AliDielectron.h
A    PWG3/dielectron/AliDielectronCFdraw.cxx
M    PWG3/dielectron/AliDielectronVarManager.h
M    PWG3/dielectron/AliAnalysisTaskDielectronFilter.cxx
M    PWG3/dielectron/AliDielectronCF.h
M    PWG3/libPWG3dielectron.pkg
M    PWG3/PWG3dielectronLinkDef.h