Add calculate page and JS

With this commit, the /calculate route works and sends the
BMI but it does not return the BMI yet.
Enable auth logic using Passport.js and Google oauth

Enable the authentication method along with the user model and the
neccesary routes. The frontpage acts ad the login entry point and
redirects to the /calculate route.
This commit also adds all the necessary configuration so Passport.js
works with policies.
Add the neccesary routes for authentication
Enable backstretch on the frontpage
Add neccesary vendor libraries and bower configuration

Included in this commit are the neccesary libraries defined by bower:
- angular
- angular-strap
- bootstrap
- angular-route
- angular-resource
- angular-backstretch (custom made)
- jquery
- angular-animate
- angular-motion
- jquery-backstretch
Configure pipeline so grunt can do its magic
Add missing libraries and Measurement server logic
Add missing protocols by Passport.js
Add empty history.ejs template
Add compiled assets
Show the history of measurements in a table at the /history route
Add compiled angular-route