move view code out of the app.rb

moves view code into erb files

* introduces instance variables - not sure if there is a better way to do this with Sinatra views?

added layout file that is a html cut and paste from http://www.pairprogramwith.me/ - not sure if that is direction UI wants to go, but seemed a good place to start 

* WARNING: currently has hardcoded and fully qualified links to all asset files on http://www.pairprogramwith.me/ 
* will want to change this before going live