Added natural sorting for documents and collections

shared/utils/naturalSort.js

@@ -0,0 +1,10 @@
+// @flow
+
+import _ from 'lodash';
+import naturalSort from 'natural-sort';
+
+export default (sortableArray: Object[], key: string) => {
+  let keys = sortableArray.map(object => object[key]);
+  keys.sort(naturalSort());
+  return _.sortBy(sortableArray, object => keys.indexOf(object[key]));
+};