add more examples for Highcharts
add open_notebook to utils.R and some minor documentation changes.
add notebook app to apps
import RJSONIO instead of rjson
initial support for Vega.
update location of notebook app
add minimum height so that xcharts svg doesn't get compressed while printing in a notebook.
correct option to options.
add .cache to .gitignore
bump version.
Merge remote-tracking branch 'ramnathv/master' into hPlot