jshint fixes in Bars.js
jshint fixes in Bars.js

ChakriCherukuri/bqplot,ChakriCherukuri/bqplot,dmadeka/bqplot,rmenegaux/bqplot,dmadeka/bqplot,ssunkara1/bqplot,bloomberg/bqplot,ChakriCherukuri/bqplot,SylvainCorlay/bqplot,SylvainCorlay/bqplot,bloomberg/bqplot,ssunkara1/bqplot,bloomberg/bqplot,rmenegaux/bqplot,SylvainCorlay/bqplot