improving ToC

Author: ducin

README.md

@@ -12,29 +12,31 @@ Check out [Swagger-Spec](https://github.com/swagger-api/swagger-spec) for additi
   - [Swagger Code Generator](#swagger-code-generator)
   - [Overview](#overview)
   - [Table of Contents](#table-of-contents)
-  - [Build and run using docker](#build-and-run-using-docker)
-  - [Build a nodejs server stub](#build-a-nodejs-server-stub)
-  - [Compatibility](#compatibility)
-  - [Prerequisites](#prerequisites)
-  - [OS X Users](#os-x-users)
-    - [Building](#building)
-  - [To generate a sample client library](#to-generate-a-sample-client-library)
-  - [Generating libraries from your server](#generating-libraries-from-your-server)
-  - [Modifying the client library format](#modifying-the-client-library-format)
-  - [Making your own codegen modules](#making-your-own-codegen-modules)
-  - [Where is Javascript???](#where-is-javascript)
-    - [Generating a client from local files](#generating-a-client-from-local-files)
-  - [Customizing the generator](#customizing-the-generator)
-  - [Validating your swagger spec](#validating-your-swagger-spec)
-  - [Generating dynamic html api documentation](#generating-dynamic-html-api-documentation)
-  - [Generating static html api documentation](#generating-static-html-api-documentation)
-  - [To build a server stub](#to-build-a-server-stub)
-    - [node.js](#nodejs)
-    - [rails-grape](#rails-grape)
-    - [scala scalatra](#scala-scalatra)
-    - [java jax-rs](#java-jax-rs)
-    - [java spring-mvc](#java-spring-mvc)
-  - [To build the codegen library](#to-build-the-codegen-library)
+  - Installation
+    - [Build and run using docker](#build-and-run-using-docker)
+    - [Build a nodejs server stub](#build-a-nodejs-server-stub)
+    - [Compatibility](#compatibility)
+    - [Prerequisites](#prerequisites)
+    - [OS X Users](#os-x-users)
+      - [Building](#building)
+  - Generators
+    - [To generate a sample client library](#to-generate-a-sample-client-library)
+    - [Generating libraries from your server](#generating-libraries-from-your-server)
+    - [Modifying the client library format](#modifying-the-client-library-format)
+    - [Making your own codegen modules](#making-your-own-codegen-modules)
+    - [Where is Javascript???](#where-is-javascript)
+      - [Generating a client from local files](#generating-a-client-from-local-files)
+    - [Customizing the generator](#customizing-the-generator)
+    - [Validating your swagger spec](#validating-your-swagger-spec)
+    - [Generating dynamic html api documentation](#generating-dynamic-html-api-documentation)
+    - [Generating static html api documentation](#generating-static-html-api-documentation)
+    - [To build a server stub](#to-build-a-server-stub)
+      - [node.js](#nodejs)
+      - [rails-grape](#rails-grape)
+      - [scala scalatra](#scala-scalatra)
+      - [java jax-rs](#java-jax-rs)
+      - [java spring-mvc](#java-spring-mvc)
+    - [To build the codegen library](#to-build-the-codegen-library)
   - [License](#license)
 
 ## Build and run using docker