add support and docs for .navbar-fixed-bottom

docs/assets/css/bootstrap.css

@@ -2840,20 +2840,26 @@ button.btn.btn-small, input[type="submit"].btn.btn-small {
   box-shadow: 0 0 3px rgba(0, 0, 0, 0.15);
   outline: 0;
 }
-.navbar-fixed-top {
+.navbar-fixed-top, .navbar-fixed-bottom {
   position: fixed;
-  top: 0;
   right: 0;
   left: 0;
   z-index: 1030;
+  margin-bottom: 0;
 }
-.navbar-fixed-top .navbar-inner {
+.navbar-fixed-top .navbar-inner, .navbar-fixed-bottom .navbar-inner {
   padding-left: 0;
   padding-right: 0;
   -webkit-border-radius: 0;
   -moz-border-radius: 0;
   border-radius: 0;
 }
+.navbar-fixed-top {
+  top: 0;
+}
+.navbar-fixed-bottom {
+  bottom: 0;
+}
 .navbar .nav {
   position: relative;
   left: 0;

docs/components.html

@@ -849,13 +849,24 @@
 </div>
 </pre>
       <h3>Fixed navbar</h3>
-      <p>To make the navbar fixed to the top of the viewport, add <code>.navbar-fixed-top</code> to the outermost div, <code>.navbar</code>.</p>
+      <p>Fix the navbar to the top or bottom of the viewport with an additional class on the outermost div, <code>.navbar</code>.</p>
+      <div class="row">
+        <div class="span4">
 <pre class="prettyprint linenums">
 &lt;div class="navbar navbar-fixed-top"&gt;
   ...
 &lt;/div&gt;
 </pre>
-      <p>In your CSS, you will also need to account for the overlap it causes by adding 40px or more of padding to your <code>&lt;body&gt;</code>. Be sure to add this after the core Bootstrap CSS and before the optional responsive CSS.</p>
+        </div><!--/span-->
+        <div class="span4">
+<pre class="prettyprint linenums">
+&lt;div class="navbar navbar-fixed-bottom"&gt;
+  ...
+&lt;/div&gt;
+</pre>
+        </div><!--/span-->
+      </div><!--/row-->
+      <p>When you affix the navbar, remember to account for the hidden area underneath. Add 40px or more of apdding to the <code>&lt;body&gt;</code>. Be sure to add this after the core Bootstrap CSS and before the optional responsive CSS.</p>
       <h3>Brand name</h3>
       <p>A simple link to show your brand or project name only requires an anchor tag.</p>
 <pre class="prettyprint linenums">

docs/templates/pages/components.mustache

@@ -773,13 +773,24 @@
 </div>
 </pre>
       <h3>{{_i}}Fixed navbar{{/i}}</h3>
-      <p>{{_i}}To make the navbar fixed to the top of the viewport, add <code>.navbar-fixed-top</code> to the outermost div, <code>.navbar</code>.{{/i}}</p>
+      <p>{{_i}}Fix the navbar to the top or bottom of the viewport with an additional class on the outermost div, <code>.navbar</code>.{{/i}}</p>
+      <div class="row">
+        <div class="span4">
 <pre class="prettyprint linenums">
 &lt;div class="navbar navbar-fixed-top"&gt;
   ...
 &lt;/div&gt;
 </pre>
-      <p>{{_i}}In your CSS, you will also need to account for the overlap it causes by adding 40px or more of padding to your <code>&lt;body&gt;</code>. Be sure to add this after the core Bootstrap CSS and before the optional responsive CSS.{{/i}}</p>
+        </div><!--/span-->
+        <div class="span4">
+<pre class="prettyprint linenums">
+&lt;div class="navbar navbar-fixed-bottom"&gt;
+  ...
+&lt;/div&gt;
+</pre>
+        </div><!--/span-->
+      </div><!--/row-->
+      <p>{{_i}}When you affix the navbar, remember to account for the hidden area underneath. Add 40px or more of apdding to the <code>&lt;body&gt;</code>. Be sure to add this after the core Bootstrap CSS and before the optional responsive CSS.{{/i}}</p>
       <h3>{{_i}}Brand name{{/i}}</h3>
       <p>{{_i}}A simple link to show your brand or project name only requires an anchor tag.{{/i}}</p>
 <pre class="prettyprint linenums">

less/navbar.less

@@ -153,22 +153,37 @@
 }
 
 
+
 // FIXED NAVBAR
 // ------------
 
-.navbar-fixed-top {
+// Shared (top/bottom) styles
+.navbar-fixed-top,
+.navbar-fixed-bottom {
   position: fixed;
-  top: 0;
   right: 0;
   left: 0;
   z-index: @zindexFixedNavbar;
+  margin-bottom: 0; // remove 18px margin for static navbar
 }
-.navbar-fixed-top .navbar-inner {
+.navbar-fixed-top .navbar-inner,
+.navbar-fixed-bottom .navbar-inner {
   padding-left:  0;
   padding-right: 0;
   .border-radius(0);
 }
 
+// Fixed to top
+.navbar-fixed-top {
+  top: 0;
+}
+
+// Fixed to bottom
+.navbar-fixed-bottom {
+  bottom: 0;
+}
+
+
 
 // NAVIGATION
 // ----------