Check_MK Werk 5483: mknotifyd: improve error handling and logging

ID: 5483 Title: mknotifyd: improve error handling and logging Component: Notifications Level: 1 Class: Bug fix Version: 1.5.0i2 Connections in progress are now explicitely written to the mknotifyd.log. This makes it easier to spot ongoning, unsucessful connection attempts. Furthermore, in case of polling errors a timeout of 1s was added. This prevents the mknotifyd from using 100% CPU if an error appears and the polling returns immediately.