Fix issue #15597 — Mention dropup variation in dropdown docs

Fix issue #15597 — Mention dropup variation in dropdown docs

Other pull request was so messed up I sincerely have no clue how to save it. The recommended command doesn't work, can't believe rebasing is so problematic...

docs/_includes/components/dropdowns.html

@@ -31,6 +31,38 @@
     <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Separated link</a></li>
   </ul>
 </div>
+{% endhighlight %}
+
+  <h3>Dropup Variation</h3> 
+  <p>Trigger dropdown menus above elements by adding <code>.dropup</code> to the parent.</p>
+
+  <h3 id="dropdowns-dropup-variation">Example</h3>
+  <div class="bs-example" data-example-id="static-dropdown">
+    <div class="dropup clearfix">
+      <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown" aria-expanded="true">
+        Dropdown
+        <span class="caret"></span>
+      </button>
+      <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu2">
+        <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Action</a></li>
+        <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Another action</a></li>
+        <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Something else here</a></li>
+      </ul>
+    </div>
+  </div><!-- /example -->
+{% highlight html %}
+<div class="dropup">
+  <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown" aria-expanded="true">
+    Dropdown
+    <span class="caret"></span>
+  </button>
+  <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu2">
+    <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Action</a></li>
+    <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Another action</a></li>
+    <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Something else here</a></li>
+    <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Separated link</a></li>
+  </ul>
+</div>
 {% endhighlight %}
 
   <h3 id="dropdowns-alignment">Alignment</h3>
@@ -53,11 +85,11 @@
   <p>Add a header to label sections of actions in any dropdown menu.</p>
   <div class="bs-example">
     <div class="dropdown clearfix">
-      <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown" aria-expanded="true">
+      <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu3" data-toggle="dropdown" aria-expanded="true">
         Dropdown
         <span class="caret"></span>
       </button>
-      <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu2">
+      <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu3">
         <li role="presentation" class="dropdown-header">Dropdown header</li>
         <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Action</a></li>
         <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Another action</a></li>
@@ -68,7 +100,7 @@
     </div>
   </div><!-- /example -->
 {% highlight html %}
-<ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu2">
+<ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu3">
   ...
   <li role="presentation" class="dropdown-header">Dropdown header</li>
   ...
@@ -104,11 +136,11 @@
   <p>Add <code>.disabled</code> to a <code>&lt;li&gt;</code> in the dropdown to disable the link.</p>
   <div class="bs-example">
     <div class="dropdown clearfix">
-      <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu3" data-toggle="dropdown" aria-expanded="true">
+      <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu4" data-toggle="dropdown" aria-expanded="true">
         Dropdown
         <span class="caret"></span>
       </button>
-      <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu3">
+      <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu4">
         <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Regular link</a></li>
         <li role="presentation" class="disabled"><a role="menuitem" tabindex="-1" href="#">Disabled link</a></li>
         <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Another link</a></li>
@@ -116,7 +148,7 @@
     </div>
   </div><!-- /example -->
 {% highlight html %}
-<ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu3">
+<ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu4">
   <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Regular link</a></li>
   <li role="presentation" class="disabled"><a role="menuitem" tabindex="-1" href="#">Disabled link</a></li>
   <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Another link</a></li>