docs(guide:directive): add directive controller usage

Specifically adding a directive controller to the example definition
and how to use declare injectables to avoid minification errors.

docs/content/guide/directive.ngdoc

@@ -269,6 +269,7 @@ Here's an example directive declared with a Directive Definition Object:
       transclude: false,
       restrict: 'A',
       scope: false,
+      controller: function($scope, $element, $attrs, $transclude, otherInjectables) { ... },
       compile: function compile(tElement, tAttrs, transclude) {
         return {
           pre: function preLink(scope, iElement, iAttrs, controller) { ... },
@@ -392,6 +393,12 @@ compiler}. The attributes are:
     * `$transclude` - A transclude linking function pre-bound to the correct transclusion scope:
       `function(cloneLinkingFn)`.
 
+    To avoid errors after minification the bracket notation should be used:
+
+    <pre>
+    controller: ['$scope', '$element', '$attrs', '$transclude', function($scope, $element, $attrs, $transclude) { ... }]
+    </pre>
+
   * `require` - Require another controller be passed into current directive linking function. The
     `require` takes a name of the directive controller to pass in. If no such controller can be
     found an error is raised. The name can be prefixed with: