Merge pull request #6 from explore-node-js/eugene-matvejev-patch-1

update README.md

Author: eugene-matvejev

README.md

@@ -1,13 +1,30 @@
 # node.js-parameter-handler
 parameter handler
 
+## how to install
+```
+npm install node.js-parameter-handler
+```
+
+
+## how to execute tests
+```
+npm test
+```
+with coverage
+```
+npm test -- --coverage
+```
 
-# how to use
+## how to use
+include configs into root package.json into 'extra' node
 
+obverve below sample of package.json
 
 ```
 # package.json
 {
+    ...
     "extra": {
         "node_parameter_handler": [
             {