This version of the ATLAS cone is coming from SpartyJet v2.20.0

We have copied the following files
  JetConeFinderTool.cxx
  JetConeFinderTool.h
  JetSplitMergeTool.cxx
  JetSplitMergeTool.h
that do the real work and based the coding in 
ATLASConePlugin.{hh,cc} on ConeFinderTool.cxx by adapting
to the ClusterSequence requirements.


copied 
  LorentzVector.{cc,hh} 
from CDFCone/CDFcode in the FastJet plugin ... then,
  - added et() == Et()
  - added e() == E

copied 
  Jet.{cc,hh}, JetDistances.hh, CommonUtils.{cc,hh}
from SpartyJet then
  - added #include <algorithm> in Jet.hh



- Cleaned a bit JetConeFinderTool.cc (mostly removed the m_log)
- Check FIXME 9 !!! (related to maxiteration)
- in #include directives, fixed the dirs
- added "namespace SpartyJet" in JetConeFinderTool.hh
- replaced StatusCode by int (as it was originally defined
- removed the string argument in the JetConeFinderTool ctor

- removed the string arg of the JetSplitMergeTool ctor
- replaced 4-vect component access using a function (e.g. px())
  with direct access (e.g. px)

IMPORTANT:
  - LorentzVector might conflict w its definition in CDFcode
  - changed the GeV to 1.0 instead of 1000.0