Cleanup assertion descriptions for _.initial()
Cleanup assertion descriptions for _.initial()

tnga/underscore-es,jpalomar/underscore,huangnan1/2016gitStudy,rlugojr/underscore,huangnan1/2016gitStudy,jdelbello/underscore,jpalomar/underscore,platinumazure/underscore,keepgoingwm/underscore,jashkenas/underscore,rlugojr/underscore,tnga/underscore-es,documentcloud/underscore,vincent1988/underscore,vincent1988/underscore,jashkenas/underscore,jdelbello/underscore,keepgoingwm/underscore,documentcloud/underscore,akre54/underscore,akre54/underscore,platinumazure/underscore