Added nosetest for computeEffectiveSampleNumber
Added nosetest for computeEffectiveSampleNumber

jchodera/pymbar,mrshirts/pymbar,jchodera/pymbar,kyleabeauchamp/pymbar,wesbarnett/pymbar,jchodera/pymbar,mrshirts/pymbar,mrshirts/pymbar,Lnaden/pymbar,kyleabeauchamp/pymbar,wesbarnett/pymbar,choderalab/pymbar,jchodera/pymbar,kyleabeauchamp/pymbar,Lnaden/pymbar,wesbarnett/pymbar,mrshirts/pymbar,Lnaden/pymbar,choderalab/pymbar,choderalab/pymbar,kyleabeauchamp/pymbar,wesbarnett/pymbar