UI (#15)

Adding new Admin UI. Updating Fredy to V3.0.0 as it has been a large rewrite. Thanks for all contributions and help on the way!

ui/src/components/logout/Logout.js

@@ -0,0 +1,21 @@
+import React from 'react';
+import { Button } from 'semantic-ui-react';
+import { xhrPost } from '../../services/xhr';
+
+const Logout = function Logout() {
+  return (
+    <Button
+      content="Logout"
+      labelPosition="left"
+      icon="user"
+      size="mini"
+      onClick={async () => {
+        await xhrPost('/api/login/logout');
+        location.reload();
+      }}
+      negative
+    />
+  );
+};
+
+export default Logout;