Change .img-polaroid to .img-thumbnail

* Same code, but different classes was confusing
* Now .img-thumbnail just extends .thumbnail

docs/assets/css/bootstrap.css

@@ -262,13 +262,17 @@ img {
   border-radius: 6px;
 }
 
-.img-polaroid {
+.img-thumbnail {
+  display: block;
+  display: inline-block;
   padding: 4px;
-  background-color: #fff;
-  border: 1px solid #ccc;
-  border: 1px solid rgba(0, 0, 0, 0.2);
-  -webkit-box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
-          box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
+  line-height: 20px;
+  border: 1px solid #ddd;
+  border-radius: 4px;
+  -webkit-transition: all 0.2s ease-in-out;
+     -moz-transition: all 0.2s ease-in-out;
+       -o-transition: all 0.2s ease-in-out;
+          transition: all 0.2s ease-in-out;
 }
 
 .img-circle {

docs/css.html

@@ -1875,12 +1875,12 @@ For example, <code><section></code> should be wrapped
           <div class="bs-docs-example bs-docs-example-images">
             <img data-src="holder.js/140x140" class="img-rounded">
             <img data-src="holder.js/140x140" class="img-circle">
-            <img data-src="holder.js/140x140" class="img-polaroid">
+            <img data-src="holder.js/140x140" class="img-thumbnail">
           </div>
 <pre class="prettyprint linenums">
 &lt;img src="..." class="img-rounded"&gt;
 &lt;img src="..." class="img-circle"&gt;
-&lt;img src="..." class="img-polaroid"&gt;
+&lt;img src="..." class="img-thumbnail"&gt;
 </pre>
 
         </section>

docs/templates/pages/css.mustache

@@ -1814,12 +1814,12 @@ For example, <code><section></code> should be wrapped
           <div class="bs-docs-example bs-docs-example-images">
             <img data-src="holder.js/140x140" class="img-rounded">
             <img data-src="holder.js/140x140" class="img-circle">
-            <img data-src="holder.js/140x140" class="img-polaroid">
+            <img data-src="holder.js/140x140" class="img-thumbnail">
           </div>
 <pre class="prettyprint linenums">
 &lt;img src="..." class="img-rounded"&gt;
 &lt;img src="..." class="img-circle"&gt;
-&lt;img src="..." class="img-polaroid"&gt;
+&lt;img src="..." class="img-thumbnail"&gt;
 </pre>
 
         </section>

less/scaffolding.less

@@ -77,13 +77,10 @@ img {
   border-radius: 6px;
 }
 
-// Add polaroid-esque trim
-.img-polaroid {
-  padding: 4px;
-  background-color: #fff;
-  border: 1px solid #ccc;
-  border: 1px solid rgba(0,0,0,.2);
-  .box-shadow(0 1px 3px rgba(0,0,0,.1));
+// Image thumbnails
+.img-thumbnail {
+  .thumbnail();
+  display: inline-block;
 }
 
 // Perfect circle