Use minification-friendly code wherever required

* When the following code is minified, it will replace all the
  variables with shorter files:

	/* Unminified */

	function($scope) {
		console.log($scope);
	}

	/* After minification */

	function(a) {
		console.log(a);
	}

	- In this example, the $scope part should not be removed, but it is.
	To avoid it, AngularJS provides a way. Instead of having just a
	function, the function should be a second element of an array; the
	first element should be the argument of the function and that should
	be a string. The correct way would be:

	[ '$scope', function($scope) {
		console.log($scope);
	}]

	- This should be done only for objects that should be referred by
	name. Like providers ($routeParams, $scope, $attrs etc.), factories
	and services (MyFactory etc.). So, a link function does not need
	this style of code whereas a controller function, does.

	Check under the 'A Note on Minification' at
	https://docs.angularjs.org/tutorial/step_05