Typescript: Add initial Typescript setup

This commit adds the initial setup for using Typescript in our project.
The tsconfig.json is very minimal at this point, we will introduce
stricter rules as our Typescript migration progresses.

tsconfig.json

@@ -0,0 +1,12 @@
+{
+  "compilerOptions": {
+    "outDir": "./dist/",
+    "noImplicitAny": true,
+    "module": "es6",
+    "target": "es5",
+    "jsx": "react-jsx",
+    "allowJs": true,
+    "moduleResolution": "node",
+    "strictNullChecks": true
+  }
+}