fix(docs): fixed angular-cli docs install guide

Author: valorkin

docs/getting-started/ng-cli.md

@@ -2,12 +2,10 @@
 
 #### Installing angular-cli
 
-*Important*: please check `angular-cli` version, it should be => "1.0.0-beta.24"
-
 *Note*: you can skip this part if you already have application generated by `ng-cli` and webpack
 
 ```bash
-npm i -g angular-cli
+npm i -g @angular/cli
 ng new my-app
 cd my-app
 ng serve