Changes

Fix client Javadoc errors currently blocking the release
The server API depends on the client API. Therefore the client API 
Javadoc may not reference (via {@link ...}) the server API Javadoc as 
that creates a circular reference. Therefore, replace all {@link ...} 
references to the server API in the client API with {@code ...}
Signed-off-by: Mark Thomas <markt@apache.org>