upgrade form-group + input-group callout from info to warning

docs/components.html

@@ -759,7 +759,7 @@ lead: "Over a dozen reusable components built to provide iconography, dropdowns,
       <h4>Tooltips &amp; popovers in input groups require special setting</h4>
       <p>When using tooltips or popovers on elements within an <code>.input-group</code>, you'll have to specify the option <code>container: 'body'</code> to avoid unwanted side effects (such as the element growing wider and/or losing its rounded corners when the tooltip or popover is triggered).</p>
     </div>
-    <div class="bs-callout bs-callout-info">
+    <div class="bs-callout bs-callout-warning">
       <h4>Don't mix with other components</h4>
       <p>Do not mix form group or grid column classes directly with input groups.</p>
     </div>