typo correction in network.py
typo correction in network.py

ljwolf/pysal,ljwolf/pysal_core,weikang9009/pysal,lanselin/pysal,TaylorOshan/pysal,jlaura/pysal,hasecbinusr/pysal,hasecbinusr/pysal,ljwolf/pysal_core,jlaura/pysal,sjsrey/pysal,ljwolf/pysal,jlaura/pysal,pastephens/pysal,hasecbinusr/pysal,lixun910/pysal,sjsrey/pysal_core,pastephens/pysal,sjsrey/pysal_core,TaylorOshan/pysal,sjsrey/pysal_core,ljwolf/pysal_core,pastephens/pysal,pedrovma/pysal,pysal/pysal,ljwolf/pysal,lixun910/pysal,lixun910/pysal,TaylorOshan/pysal