Updated documentation and add .env.example file with the correct parameter names

Author: w0o

README.md

@@ -39,6 +39,8 @@ var recognizeMic = require('watson-speech/speech-to-text/recognize-microphone');
 
 This SDK _CAN_ be used in the browser with services that use IAM for authentication. This does require a server-side component - an endpoint used to retrieve the token. An example can be found [here](https://github.com/watson-developer-cloud/speech-javascript-sdk/blob/master/examples/server.js#L92).
 
+In a local environment you should set only the TEXT_TO_SPEECH_IAM_APIKEY and SPEECH_TO_TEXT_IAM_APIKEY in your .env file, see example file [here](https://github.com/watson-developer-cloud/speech-javascript-sdk/blob/master/examples/.env.example).
+
 Once that is set up, the token can be used in your SDK request with the parameter `access_token`. See [this example](https://github.com/watson-developer-cloud/speech-javascript-sdk/blob/master/examples/static/microphone-streaming.html#L36).
 
 ## Changes

examples/.env.example

@@ -0,0 +1,6 @@
+SPEECH_TO_TEXT_IAM_APIKEY=""
+SPEECH_TO_TEXT_USERNAME=""
+SPEECH_TO_TEXT_PASSWORD=""
+TEXT_TO_SPEECH_IAM_APIKEY=""
+TEXT_TO_SPEECH_USERNAME=""
+TEXT_TO_SPEECH_PASSWORD=""