add an R mode to the rcharts notebook app.
use a dropdown for selecting mode (rmd/r)
modify the keyboard shortcuts.
Merge pull request #95 from reinholdsson/hPlot

Updates to Highcharts/hPlot
Merge github.com:ramnathv/rCharts
bump version to 0.3.1
use rcharts viewer instead of pagist.
add support for fullscreen in leaflet.
add id argument to publish method to update gists.
add add_lib argument to showOutput so that it can used inside Slidify.
add digits = 13 to prevent conversion to scientific notation. think of making it the default for toJSON2.
load rCharts in ui.R in notebook.
activate circle method in Leaflet (preliminary)
bump version to 0.3.2
allow charts published on rpubs to be updated. fixes #107
return the gist id invisibly
return the html_id invisibly while publishing as gist.
automatically add the gist id to the chart so that subsequent changes are updates.
add map height and width  in renderMap.
added templates field to rCharts class
Initialized page template to chart.html and chartDiv to NULL. Libraries can override based on their needs.