Add a 'Delete Schedule' function to the 'Set Run-time' Modal Window

Current Situation

• A Schedule set at Run-time can only be deleted by either editing the XML or by using the Reset Run-time. There is no direct 'Delete Schedule' button.
• The 'Set Run-time' modal window uses the expression 'Run-time' when 'Frequency' is meant. This is somewhat confusing.
• It is easy to overlook that a Schedule has been set when opening the 'Set Run-time' modal window - the default setting is that the window opens with 'Run-time', even when a Schedule has been set.

Desired Behaviour

• A 'Delete Schedule' function should be added to the 'Set Run-time' modal window.
• The 'Run-time' fields in the 'Set Run-time' modal window should be changed to 'Frequency'.
• The 'Set Run-time' modal window should open with 'Schedule' selected, when a Schedule has already been selected.