Revise README

Add NodeJS and Splunk versions tested for compatibility
https://jira.splunk.com/browse/DVPL-7485

Author: PKing70

README.md

@@ -7,6 +7,11 @@ The Splunk Software Development Kit (SDK) for JavaScript contains library code a
 examples designed to enable developers to build applications using Splunk and
 JavaScript. This SDK supports both server- and client-side JavaScript.
 
+## Requirements
+
+* Node.js v0.10, v.0.12, or v4 or later. The Splunk SDK for Javascript is tested with Node.js v0.10, v.0.12, v4.2, and v10.0. 
+* Splunk Enterprise 6.3.0 or later, or Splunk Cloud. The Splunk SDK for Javascript is tested with Splunk Enterprise 7.0 and 7.2. 
+
 ## Installation
 
 This section describes the basic steps for installing the Splunk SDK for JavaScript.