add index.md

Author: hantsy

.gitignore

@@ -34,3 +34,5 @@ lerna-debug.log*
 !.vscode/extensions.json
 
 .env
+.metals
+.vscode

docs/api.md

@@ -0,0 +1,9 @@
+# Building RESTful APIs with NestJS
+
+* [Getting Started](./docs/guide.md)
+* [Connecting to MongoDB](./docs/mongo.md)
+* [Protect your APIs with JWT Token](./docs/auth.md)
+* [Dealing with model relations](./docs/model.md)
+* [Externalizing the configuration](./docs/config.md)
+* [Handling user registration](./docs/user.md)
+* [Testing Nestjs applications](./docs/testing.md)