GUACAMOLE-195: Add RAT plugin to extension; fix build issue from leftover logger() call.

extensions/guacamole-auth-http/src/main/java/org/apache/guacamole/auth/http/AuthenticationProviderService.java

@@ -75,7 +75,6 @@ public class AuthenticationProviderService {
                 username = request.getHeader(confService.getHttpAuthHeader());
 
             if (username != null) {
-                logger.debug("Authenticating with user {}", username);
                 AuthenticatedUser authenticatedUser = authenticatedUserProvider.get();
                 authenticatedUser.init(username, credentials);
                 return authenticatedUser;