[ci-skip] fixed typos in readme

README.md

@@ -55,15 +55,15 @@ var credentials = vcapServices.getCredentials('personality_insights', 'standard'
 console.log(credentials);
 ```
 
-### Getting credentials for a specific intsance
+### Getting credentials for a specific instance
 Get credentials that match a specific service instance (replace "YOUR NLC NAME" with the name of your service instance).
 ```sh
 var vcapServices = require('vcap_services');
 var credentials = vcapServices.getCredentials('natural_language_classifier', null, 'YOUR NLC NAME');
 console.log(credentials);
 ```
 
-### Getting credentials for a specific plan and intsance
+### Getting credentials for a specific plan and instance
 Get credentials that match a specific service plan and instance (replace "YOUR NLC NAME" with the name of your service instance).
 ```sh
 var vcapServices = require('vcap_services');