add Prettier & Visual Studio Code settings and recommendations

.prettierrc.json

+{
+  "trailingComma": "all",
+  "singleQuote": true
+}

.vscode/extensions.json

+{
+  "recommendations": ["esbenp.prettier-vscode"]
+}

.vscode/settings.json

+{
+  "editor.formatOnSave": true,
+  "prettier.disableLanguages": ["html"]
+}

tslint.json

@@ -23,7 +23,8 @@
     "import-spacing": true,
     "indent": [
       true,
-      "tabs"
+      "spaces",
+      2
     ],
     "interface-over-type-literal": true,
     "label-position": true,