Fixed regression with Panels caused by NDFrame not checking if it was  DataFrame before assuming it had a 'columns' attribute. 
Fixed regression with Panels caused by NDFrame not checking if it was  DataFrame before assuming it had a 'columns' attribute. 
louispotok/pandas,cython-testbed/pandas,louispotok/pandas,jmmease/pandas,harisbal/pandas,cbertinato/pandas,zfrenchee/pandas,toobaz/pandas,zfrenchee/pandas,zfrenchee/pandas,winklerand/pandas,DGrady/pandas,gfyoung/pandas,kdebrab/pandas,nmartensen/pandas,MJuddBooth/pandas,GuessWhoSamFoo/pandas,jreback/pandas,linebp/pandas,linebp/pandas,rs2/pandas,toobaz/pandas,MJuddBooth/pandas,datapythonista/pandas,dsm054/pandas,nmartensen/pandas,pratapvardhan/pandas,DGrady/pandas,jreback/pandas,TomAugspurger/pandas,winklerand/pandas,GuessWhoSamFoo/pandas,cbertinato/pandas,DGrady/pandas,pratapvardhan/pandas,cbertinato/pandas,nmartensen/pandas,linebp/pandas,linebp/pandas,pratapvardhan/pandas,harisbal/pandas,amolkahat/pandas,jorisvandenbossche/pandas,jreback/pandas,TomAugspurger/pandas,amolkahat/pandas,GuessWhoSamFoo/pandas,cython-testbed/pandas,nmartensen/pandas,kdebrab/pandas,winklerand/pandas,kdebrab/pandas,cbertinato/pandas,datapythonista/pandas,dsm054/pandas,dsm054/pandas,louispotok/pandas,pandas-dev/pandas,dsm054/pandas,MJuddBooth/pandas,nmartensen/pandas,gfyoung/pandas,DGrady/pandas,cython-testbed/pandas,kdebrab/pandas,Winand/pandas,rs2/pandas,gfyoung/pandas,Winand/pandas,DGrady/pandas,cython-testbed/pandas,jmmease/pandas,amolkahat/pandas,GuessWhoSamFoo/pandas,jreback/pandas,jmmease/pandas,harisbal/pandas,harisbal/pandas,jorisvandenbossche/pandas,pandas-dev/pandas,rs2/pandas,toobaz/pandas,TomAugspurger/pandas,datapythonista/pandas,Winand/pandas,DGrady/pandas,winklerand/pandas,cbertinato/pandas,jorisvandenbossche/pandas,winklerand/pandas,dsm054/pandas,GuessWhoSamFoo/pandas,zfrenchee/pandas,louispotok/pandas,Winand/pandas,toobaz/pandas,MJuddBooth/pandas,jmmease/pandas,jmmease/pandas,toobaz/pandas,winklerand/pandas,pratapvardhan/pandas,TomAugspurger/pandas,zfrenchee/pandas,pratapvardhan/pandas,amolkahat/pandas,jmmease/pandas,gfyoung/pandas,amolkahat/pandas,jorisvandenbossche/pandas,Winand/pandas,gfyoung/pandas,louispotok/pandas,Winand/pandas,pandas-dev/pandas,linebp/pandas,datapythonista/pandas,MJuddBooth/pandas,jreback/pandas,rs2/pandas,pandas-dev/pandas,linebp/pandas,cython-testbed/pandas,harisbal/pandas,nmartensen/pandas,kdebrab/pandas