Merge pull request OAI#952 from OAI/update-version

update version

Author: webron

versions/3.0.md

@@ -1,6 +1,6 @@
 # OpenAPI Specification
 
-#### Version 3.0
+#### Version 3.0.0-rc0
 
 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC 2119](http://www.ietf.org/rfc/rfc2119.txt).