deconflict bar-plot.css with form element in bootstrap_form.css
no more raw data on bar_plot
merge line-plot and bar-plot d3 stuff so they look similar
pug common code in plot-util.d3.js
mouseover text works but headers must be valid javascript variable names
better styled tooltips
mouse events pass through tooltip
Merge branch 'master' of github.com:hobson/pug