[RFE] Multiple date/time elements in a service dialog

Issue

• Ability to select a start date and end date for some of our dialogs. Currently selecting a start date and the number of hours until the method retries. However, this isn't ideal situation therefore should be able to select an end date as well.
• Ability to select a time period for virtual machines to be put into maintenance mode. Currently selecting a start date and a number for days to remain in maintenance mode. Instead of this approach, there should be option to select a start date and end date.