Merge pull request #162 from leotm/patch-1

Update README.md

Author: dmitry-zaets

README.md

@@ -9,10 +9,16 @@ Please note that this library is designed to test the action-related logic, not
 
 ## Install
 
-```
+```bash
 npm install redux-mock-store --save-dev
 ```
 
+Or
+
+```bash
+yarn add redux-mock-store --dev
+```
+
 ## Usage
 
 ### Synchronous actions