Install CoffeeScript Rails Source Maps

Adds CoffeeScript source maps support, introduced in version 1.6.1, to
Rails.
Add RVM stuff

Through the use of .powrc file enable Pow to read RVM configurations.
Update README
Dynamically load SECRET_KEY_BASE environment variable
Configure Capistrano
Scaffold landing page
Basic launching mechanism
Start the receiver code
Autoclose window
Limit number of kept deployments
Store Chromecast App ID in environment var
Load available receivers
Bug in getResultCallback
Launch application on Chromecast
Cleanup the receiver page
Reorganize sender assets
Reorganize receiver assets