Add icon-inline component, update render-heading.html.example and add render-image.html.example.

assets/sass/components/icon-inline/_icon-inline.scss

@@ -0,0 +1,27 @@
+// Inline icons.
+
+.icon-inline,
+%icon-inline {
+  .icon-link {
+    opacity: 0;
+    transition: all 130ms ease-in;
+    text-decoration: none;
+  }
+
+  &:focus,
+  &:hover {
+    .icon-link {
+      opacity: .3;
+
+      &:focus,
+      &:hover {
+        opacity: 1;
+      }
+    }
+  }
+
+  svg {
+    display: inline;
+    vertical-align: middle;
+  }
+}