Convert to TypeScript

Summary: Converted the Crash Reporter plugin to Typescript while fixing all linting errors

Reviewed By: jknoxville

Differential Revision: D22571332

fbshipit-source-id: d3092ffc480827b5eb1beb5c3cc91dad6993e267

desktop/plugins/crash_reporter/unicode-substring.d.tsx

@@ -0,0 +1,17 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+declare module 'unicode-substring' {
+  const unicodeSubstring: (
+    string: string,
+    start: number,
+    end: number,
+  ) => string;
+  export default unicodeSubstring;
+}