added settings tab, add language chooser

src/shared/Dropdown.js

@@ -0,0 +1,25 @@
+import React from 'react';
+
+const Dropdown = ({ label, value, onChange, options, optionItem }) => (
+  <div className="flex flex-col mb-2">
+    {label && (
+      <label className="uppercase tracking-wide text-gray-600 text-xs font-semibold mb-2">
+        {label}
+      </label>
+    )}
+    <div className="inline-flex relative w-full bg-gray-200 text-gray-800 rounded py-3 px-4 leading-tight focus:outline-none">
+      <select
+        className="block appearance-none w-full bg-gray-200 text-gray-800 focus:outline-none"
+        value={value}
+        onChange={e => onChange(e.target.value)}
+      >
+        {options.map(optionItem)}
+      </select>
+      <div className="pointer-events-none absolute inset-y-0 right-0 flex justify-center items-center px-2 bg-gray-200">
+        <i className="material-icons">expand_more</i>
+      </div>
+    </div>
+  </div>
+);
+
+export default Dropdown;