Update version number in README.md

Author: pasin

README.md

@@ -1,6 +1,5 @@
 
-# Couchbase Lite 2.0 (Beta)
-
+# Couchbase Lite 2.0
 **Couchbase Lite** is an embedded lightweight, document-oriented (NoSQL), syncable database engine.
 
 Couchbase Lite 2.0 has a completely new set of APIs. The implementation is on top of [Couchbase Lite Core](https://github.com/couchbase/couchbase-lite-core), which is also a new cross-platform implementation of database CRUD and query features, as well as document versioning.