implemented deepcopy for ROD, see #237
implemented deepcopy for ROD, see #237

ljwolf/pysal_core,dfolch/pysal,darribas/pysal,hasecbinusr/pysal,jlaura/pysal,ljwolf/pysal_core,pedrovma/pysal,schmidtc/pysal,darribas/pysal,sjsrey/pysal_core,ljwolf/pysal,hasecbinusr/pysal,TaylorOshan/pysal,lixun910/pysal,sjsrey/pysal_core,pastephens/pysal,pastephens/pysal,spreg-git/pysal,nathania/pysal,badjr/pysal,dfolch/pysal,ljwolf/pysal,jlaura/pysal,chhao91/pysal,sjsrey/pysal,badjr/pysal,hasecbinusr/pysal,sjsrey/pysal_core,lixun910/pysal,schmidtc/pysal,spreg-git/pysal,chhao91/pysal,weikang9009/pysal,jlaura/pysal,TaylorOshan/pysal,nathania/pysal,ljwolf/pysal_core,TaylorOshan/pysal,pastephens/pysal,pysal/pysal,lanselin/pysal,ljwolf/pysal,lixun910/pysal