- fixing bug luc identified with regard to mean_neighbor property. wrong key   name was used in cache dictionary.
- fixing bug luc identified with regard to mean_neighbor property. wrong key
  name was used in cache dictionary.

AlanZatarain/pysal,tectronics/pysal,tectronics/pysal,AlanZatarain/pysal,AlanZatarain/pysal,Alwnikrotikz/pysal,Alwnikrotikz/pysal,Alwnikrotikz/pysal,tectronics/pysal