Stylize images with borders and captions

Taken from https://css-tricks.com/give-your-images-space-and-captions-for-better-layout/ and adapted to be a Hugo render hook.

Signed-off-by: Harsh Shandilya <msfjarvis@gmail.com>

layouts/_default/_markup/render-image.html

@@ -0,0 +1,4 @@
+<div class="image_caption">
+  <img src="{{ .Destination | safeURL }}" alt="{{ .Text }}" />
+  <p>{{ .Text }}</p>
+</div>

themes/hyde/assets/css/poole.css

@@ -82,6 +82,16 @@ a:focus {
   text-decoration: underline;
 }
 
+div.image_caption {
+  display: inline-block;
+  padding: 10px;
+  margin: 10px;
+  border: 2px solid #cccccc;
+  text-align: center;
+  font-size: 0.8em;
+  font-style: italic;
+}
+
 .tag {
   color: #757575;
 }