Checkmk Werk 12704: Do not create Carbon data if no connection is configured

ID: 12704 Title: Do not create Carbon data if no connection is configured Component: Core & setup Level: 1 Class: Bug fix Version: 2.2.0i1 The core would create and enqueue data for the Carbon connection even if none is configured. This may incur a small performance penalty and, provided the site generates a large amount of data, log messages such as <tt>[carbon connection pool] queue full, didn't push update</tt> that are irrelevant. This fix only sends data to the Carbon connection if necessary.