In TTreePlayer::DrawSelect, simplify the logic when the binning info

is specified in the query and add support for the limits as indicated
in the function comments.
  T.Draw("px>>hpx(50,-2,3)")
is again working after this change.


git-svn-id: http://root.cern.ch/svn/root/trunk@3785 27541ba8-7e3a-0410-8455-c3a389f83636