BUG: Test for underlying price before reducing data
BUG: Test for underlying price before reducing data

Removed most references to month and year (passing expiry date around instead).
Also protected with RemoteDataError checking for the expiry month links.

Winand/pandas,amolkahat/pandas,harisbal/pandas,rs2/pandas,gfyoung/pandas,toobaz/pandas,cbertinato/pandas,jmmease/pandas,MJuddBooth/pandas,jorisvandenbossche/pandas,jreback/pandas,datapythonista/pandas,louispotok/pandas,zfrenchee/pandas,TomAugspurger/pandas,DGrady/pandas,DGrady/pandas,Winand/pandas,kdebrab/pandas,jreback/pandas,rs2/pandas,datapythonista/pandas,DGrady/pandas,harisbal/pandas,TomAugspurger/pandas,cython-testbed/pandas,cython-testbed/pandas,pandas-dev/pandas,TomAugspurger/pandas,pratapvardhan/pandas,DGrady/pandas,pandas-dev/pandas,winklerand/pandas,louispotok/pandas,zfrenchee/pandas,pandas-dev/pandas,dsm054/pandas,jmmease/pandas,linebp/pandas,Winand/pandas,zfrenchee/pandas,nmartensen/pandas,MJuddBooth/pandas,gfyoung/pandas,datapythonista/pandas,zfrenchee/pandas,toobaz/pandas,jmmease/pandas,GuessWhoSamFoo/pandas,nmartensen/pandas,datapythonista/pandas,louispotok/pandas,Winand/pandas,DGrady/pandas,toobaz/pandas,jmmease/pandas,jorisvandenbossche/pandas,cython-testbed/pandas,kdebrab/pandas,GuessWhoSamFoo/pandas,jorisvandenbossche/pandas,jmmease/pandas,amolkahat/pandas,gfyoung/pandas,jreback/pandas,toobaz/pandas,nmartensen/pandas,winklerand/pandas,winklerand/pandas,cbertinato/pandas,Winand/pandas,dsm054/pandas,cython-testbed/pandas,harisbal/pandas,toobaz/pandas,winklerand/pandas,gfyoung/pandas,pratapvardhan/pandas,louispotok/pandas,zfrenchee/pandas,MJuddBooth/pandas,TomAugspurger/pandas,jreback/pandas,winklerand/pandas,nmartensen/pandas,jreback/pandas,dsm054/pandas,linebp/pandas,kdebrab/pandas,louispotok/pandas,pratapvardhan/pandas,dsm054/pandas,linebp/pandas,pratapvardhan/pandas,winklerand/pandas,linebp/pandas,cbertinato/pandas,harisbal/pandas,MJuddBooth/pandas,jmmease/pandas,cbertinato/pandas,MJuddBooth/pandas,Winand/pandas,kdebrab/pandas,pandas-dev/pandas,cython-testbed/pandas,GuessWhoSamFoo/pandas,dsm054/pandas,amolkahat/pandas,rs2/pandas,cbertinato/pandas,GuessWhoSamFoo/pandas,amolkahat/pandas,rs2/pandas,harisbal/pandas,amolkahat/pandas,nmartensen/pandas,pratapvardhan/pandas,linebp/pandas,gfyoung/pandas,jorisvandenbossche/pandas,GuessWhoSamFoo/pandas,linebp/pandas,kdebrab/pandas,DGrady/pandas,nmartensen/pandas