[cellcentered] cleanup ccfvelementgeometry

Remove unused include and enums. Corrected enums to match cellcentered geometry.
The enums were still matched to the box method causing a memory overhead for the cellcentered.
Cellcentered methods should now need less allocated memory. Question remains if vector sizes 
in element geometry have to be variable (hanging nodes and low dimensional grids)

Reviewed by bernd
  


git-svn-id: svn://svn.iws.uni-stuttgart.de/DUMUX/dumux/trunk@14233 2fb0f335-1f38-0410-981e-8018bf24f1b0