docs(guide/accessibility): fix links

Author: gkalpak

docs/content/guide/accessibility.ngdoc

@@ -41,7 +41,7 @@ Currently, ngAria interfaces with the following directives:
 
 <h2 id="ngmodel">ngModel</h2>
 
-Much of ngAria's heavy lifting happens in the {@link ng/directive/ngModel}
+Much of ngAria's heavy lifting happens in the {@link ng.directive:ngModel ngModel}
 directive. For elements using ngModel, special attention is paid by ngAria if that element also
 has a role or type of `checkbox`, `radio`, `range` or `textbox`.
 
@@ -141,7 +141,7 @@ it with your keyboard and at least one mobile and desktop screen reader.
 
 The `disabled` attribute is only valid for certain elements such as `button`, `input` and
 `textarea`. To properly disable custom element directives such as `<md-checkbox>` or `<taco-tab>`,
-using ngAria with {@link ng/directive/ngDisabled} will also
+using ngAria with {@link ng.directive:ngDisabled ngDisabled} will also
 add `aria-disabled`. This tells assistive technologies when a non-native input is disabled, helping
 custom controls to be more accessible.
 
@@ -162,7 +162,7 @@ Becomes:
 
 <h2 id="ngshow">ngShow</h2>
 
->The {@link ng/directive/ngShow} directive shows or hides the
+>The {@link ng.directive:ngShow ngShow} directive shows or hides the
 given HTML element based on the expression provided to the `ngShow` attribute. The element is
 shown or hidden by removing or adding the `.ng-hide` CSS class onto the element.
 
@@ -199,7 +199,7 @@ Becomes:
 
 <h2 id="nghide">ngHide</h2>
 
->The {@link ng/directive/ngHide} directive shows or hides the
+>The {@link ng.directive:ngHide ngHide} directive shows or hides the
 given HTML element based on the expression provided to the `ngHide` attribute. The element is
 shown or hidden by removing or adding the `.ng-hide` CSS class onto the element.