Move external static content into external directory

app/static/external/material-design-icons/css/material-icons.css

@@ -0,0 +1,37 @@
+@font-face {
+  font-family: "Material Icons";
+  font-style: normal;
+  font-weight: 400;
+  /* For IE6-8 */
+  /* src: url("../font/MaterialIcons-Regular.eot"); */
+  src: local("Material Icons"),
+    local("MaterialIcons-Regular"),
+    /* url("../font/MaterialIcons-Regular.woff2") format('woff2'), */
+    /* url("../font/MaterialIcons-Regular.woff") format('woff'), */
+    url("../font/MaterialIcons-Regular.ttf") format("truetype");
+}
+
+.material-icons {
+  font-family: 'Material Icons';
+  font-weight: normal;
+  font-style: normal;
+  font-size: 24px;  /* Preferred icon size */
+  display: inline-block;
+  line-height: 1;
+  text-transform: none;
+  letter-spacing: normal;
+  word-wrap: normal;
+  white-space: nowrap;
+  direction: ltr;
+
+  /* Support for all WebKit browsers. */
+  -webkit-font-smoothing: antialiased;
+  /* Support for Safari and Chrome. */
+  text-rendering: optimizeLegibility;
+
+  /* Support for Firefox. */
+  -moz-osx-font-smoothing: grayscale;
+
+  /* Support for IE. */
+  font-feature-settings: 'liga';
+}