Fixed typo in release notes.

README.md

@@ -7,7 +7,7 @@ the license server can help teams knowing how many licenses they actually use.
 
 The license server is a classic ASP.NET application with an MS SQL back-end.
 
-We at PostSharp consider that it is the customer's sole responsibility to respect the license agreement, and this is why we are providing the source code of the license server. Note that the use of licenses keys [are audited anyway](http://doc.postsharp.net/license-audit); if this is not an option for your organization, you can ask the PostSharp sales team for a license key with audit waiver.
+We at PostSharp consider that it is the customer's sole responsibility to respect the license agreement, and this is why we are providing the source code of the license server. Note that the use of licenses keys [is audited anyway](http://doc.postsharp.net/license-audit); if this is not an option for your organization, you can ask the PostSharp sales team for a license key with audit waiver.
 
 ## License