add docs for #13745

Good catch @juthilo
[skip sauce]

docs/_includes/css/forms.html

@@ -207,7 +207,8 @@
 {% endhighlight %}
 
   <h3>Checkboxes and radios</h3>
-  <p>Checkboxes are for selecting one or several options in a list while radios are for selecting one option from many.</p>
+  <p>Checkboxes are for selecting one or several options in a list, while radios are for selecting one option from many.</p>
+  <p>A checkbox or radio with the <code>disabled</code> attribute will be styled appropriately. To have the <code>&lt;label&gt;</code> for the checkbox or radio also display a "not-allowed" cursor when the user hovers over the label, add the <code>.disabled</code> class to your <code>.radio</code>, <code>.radio-inline</code>, <code>.checkbox</code>, <code>.checkbox-inline</code>, or <code>&lt;fieldset&gt;</code>.</p>
   <h4>Default (stacked)</h4>
   <div class="bs-example">
     <form role="form">
@@ -217,6 +218,12 @@
           Option one is this and that&mdash;be sure to include why it's great
         </label>
       </div>
+      <div class="checkbox disabled">
+        <label>
+          <input type="checkbox" value="" disabled>
+          Option two is disabled
+        </label>
+      </div>
       <br>
       <div class="radio">
         <label>
@@ -230,6 +237,12 @@
           Option two can be something else and selecting it will deselect option one
         </label>
       </div>
+      <div class="radio disabled">
+        <label>
+          <input type="radio" name="optionsRadios" id="optionsRadios3" value="option3" disabled>
+          Option three is disabled
+        </label>
+      </div>
     </form>
   </div><!-- /.bs-example -->
 {% highlight html %}
@@ -239,6 +252,12 @@
     Option one is this and that&mdash;be sure to include why it's great
   </label>
 </div>
+<div class="checkbox disabled">
+  <label>
+    <input type="checkbox" value="" disabled>
+    Option two is disabled
+  </label>
+</div>
 
 <div class="radio">
   <label>
@@ -252,6 +271,12 @@
     Option two can be something else and selecting it will deselect option one
   </label>
 </div>
+<div class="radio disabled">
+  <label>
+    <input type="radio" name="optionsRadios" id="optionsRadios3" value="option3" disabled>
+    Option three is disabled
+  </label>
+</div>
 {% endhighlight %}
 
   <h4>Inline checkboxes and radios</h4>