Build "Add to calendar" functionality

[GriffinSauce]

https://developers.google.com/google-apps/calendar/?csw=1 http://developers.google.com/apis-explorer/#p/calendar/v3/

[GriffinSauce]

Being a webapp sucks. There is no way to reliably provide a calendar event for Android.

So:

• Provide a .ics file for iPhone users
• Connect to Google Calendar and inject automatically (is a more elegant solution anyways)

https://www.npmjs.com/package/google-calendar

[GriffinSauce]

Moving this to a later release so we can focus on workflow first.