Merge pull request nestjs#2592 from Tony133/docs/update-snippets-code

docs(cli): update snippets code

Author: kamilmysliwiec

content/cli/libraries.md

@@ -19,7 +19,7 @@ Any functionality that is suitable for re-use is a candidate for being managed a
 To get started with creating a library, run the following command:
 
 ```bash
-nest g library my-library
+$ nest g library my-library
 ```
 
 When you run the command, the `library` schematic prompts you for a prefix (AKA alias) for the library:
@@ -78,7 +78,7 @@ As with application-type projects, libraries each have their own `tsconfig.lib.j
 You can build the library with the CLI command:
 
 ```bash
-nest build my-library
+$ nest build my-library
 ```
 
 #### Using libraries

content/cli/workspaces.md

@@ -26,7 +26,7 @@ To enable monorepo mode, you start with a _standard mode_ structure, and add **p
 If we run:
 
 ```bash
-nest new my-project
+$ nest new my-project
 ```
 
 We've constructed a _standard mode_ structure, with a folder structure that looks like this:
@@ -49,8 +49,8 @@ We've constructed a _standard mode_ structure, with a folder structure that look
 We can convert this to a monorepo mode structure as follows:
 
 ```bash
-cd my-project
-nest generate app my-app
+$ cd my-project
+$ nest generate app my-app
 ```
 
 At this point, `nest` converts the existing structure to a **monorepo mode** structure. This results in a few important changes. The folder structure now looks like this: