JOC Cockpit History customization should include relative execution dates

Current Situation

• When creating a customization for the History from the advanced search then the user has to enter a specific date. This is fine for the advanced search, it is not ok for later use of a customization.
• A user can add a relative execution date, e.g. now-2d, only when editing the customization, see history_customization.png screenshot.

Desired Behavior

• The advanced search should include the "Process executed" input field in the same way as it is available when editing a customization.