Re-incorporating client_side_validations into the app

Not only is this a better way to do validations, it also allows us to
auto-login users on registration

Previously, our forms used AJAX and validations were server side (returning a JSON).
But to auto-login, we need to call redirect_to. Its not possible to call both
redirect_to and render :json together. Hence, the need to separate the
two - validations and auto-login
No need to pass :server as a local variable to _register partial
Validate presence of name - and not just the first name
[Big one]: Auto-login on registration ...

Enabling auto-login isnt too tough - per say. Simply requires calls to sign_in
and redirect_to

But validations proved to be the sore thumb. Hence, needed to incorporate
client_side_validations
Merge branch 'master' of github.com:abhinavc/web-application + resolved conflicts

Conflicts:
	app/assets/javascripts/core/response.js.coffee
	app/controllers/students_controller.rb
	app/controllers/teachers_controller.rb
	app/views/modals/user/_register.html.haml