Add Versions section to README

Author: driverdan

README.md

@@ -1,11 +1,14 @@
 # node-XMLHttpRequest #
 
-node-XMLHttpRequest is a wrapper for the built-in http client to emulate the browser XMLHttpRequest object.
+node-XMLHttpRequest is a wrapper for the built-in http client to emulate the
+browser XMLHttpRequest object.
 
-This can be used with JS designed for browsers to improve reuse of code and allow the use of existing libraries.
+This can be used with JS designed for browsers to improve reuse of code and
+allow the use of existing libraries.
 
 ## Usage ##
-Here's how to include the module in your project and use as the browser-based XHR object.
+Here's how to include the module in your project and use as the browser-based
+XHR object.
 
 	var XMLHttpRequest = require("xmlhttprequest").XMLHttpRequest;
 	var xhr = new XMLHttpRequest();
@@ -15,6 +18,17 @@ case-sensitive systems (eg Linux) using uppercase letters won't work.
 
 Refer to [W3C specs](http://www.w3.org/TR/XMLHttpRequest/) for XHR methods.
 
+## Versions ##
+
+Prior to 1.4.0 version numbers were arbitrary. From 1.4.0 on they conform to
+the standard major.minor.bugfix. 1.x shouldn't necessarily be considered
+stable just because it's above 0.x.
+
+Since the XMLHttpRequest API is stable this library's API is stable as
+well. Major version numbers indicate significant core code changes.
+Minor versions indicate minor core code changes or better conformity to
+the W3C spec.
+
 ## Supports ##
 
 * Async and synchronous requests