Checkmk Werk 12070: Fix creation of timeperiod copy

ID: 12070 Title: Fix creation of timeperiod copy Component: Multisite Level: 1 Class: Bug fix Version: 2.1.0i1 If an existing timeperiod was cloned via "Create a copy", the values of the existing, copied timeperiod were changed. No new timeperiod was created. Creating a copy will now create a clone of the chosen timeperiod. Furthermore, if you create a new timeperiod, the "Internal ID" will be pre-filled.