docs(installation): remove outdated installation instruction

docs_app/content/guide/installation.md

@@ -26,33 +26,19 @@ To import only what you need, please {@link guide/importing#es6-via-npm check ou
 
 ## CommonJS via npm
 
-If you receive an error like error TS2304: Cannot find name 'Promise' or error TS2304: Cannot find name
-'Iterable' when using RxJS you may need to install a supplemental set of typings.
+If you receive an error like `error TS2304: Cannot find name 'Promise'` or `error TS2304: Cannot find name
+'Iterable'` when using RxJS you may need to install a supplemental set of typings.
 
 1.  For typings users:
 
-```shell
-typings install es6-shim --ambient
-```
+  ```shell
+  typings install es6-shim --ambient
+  ```
 
-2.  If you're not using typings the interfaces can be copied from /es6-shim/es6-shim.d.ts.
+2.  If you're not using typings the interfaces can be copied from `/es6-shim/es6-shim.d.ts`.
 
 3.  Add type definition file included in tsconfig.json or CLI argument.
 
-## All Module Types (CJS/ES6/AMD/TypeScript) via npm
-
-To install this library via npm version 3, use the following command:
-
-```shell
-npm install @reactivex/rxjs
-```
-
-If you are using npm version 2, you need to specify the library version explicitly:
-
-```shell
-npm install @reactivex/[email protected]
-```
-
 ## CDN
 
 For CDN, you can use [unpkg](https://unpkg.com/):