Add doc/guide.md

package.json

@@ -45,6 +45,7 @@
     "@types/ws": "^6.0.4",
     "@typescript-eslint/eslint-plugin": "^2.0.0",
     "@typescript-eslint/parser": "^2.0.0",
+    "doctoc": "^1.4.0",
     "eslint": "^6.2.0",
     "eslint-config-prettier": "^6.0.0",
     "eslint-plugin-import": "^2.18.2",
@@ -52,7 +53,7 @@
     "leaked-handles": "^5.2.0",
     "mocha": "^6.2.0",
     "parcel-bundler": "^1.12.4",
-    "prettier": "^1.18.2",
+    "prettier": "^2.0.5",
     "stylelint": "^13.0.0",
     "stylelint-config-recommended": "^3.0.0",
     "ts-node": "^8.4.1",