UI infrastructure and simple "Help" dialog (#3)

Sets up some WIP infrastructure for building out the UI, and adds a simple popup
to show the navigation controls for the app.

framework/tsconfig.json

@@ -0,0 +1,22 @@
+{
+  "extends": "../tsconfig.base.json",
+  "compilerOptions": {
+    "module": "commonjs",
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "noImplicitOverride": true,
+    "noPropertyAccessFromIndexSignature": true,
+    "noImplicitReturns": true,
+    "noFallthroughCasesInSwitch": true
+  },
+  "files": [],
+  "include": [],
+  "references": [
+    {
+      "path": "./tsconfig.lib.json"
+    },
+    {
+      "path": "./tsconfig.spec.json"
+    }
+  ]
+}