[Feature request] Add a TimeSpan editor - similar to TimePicker

Is your feature request related to a problem? Please describe.
The TimePicker control binds to a DateTime and only allows the specification of a 24-hour time. Further, the PropertyGrid cannot bind to a TimeSpan and there is no suitable editor built-in.

Describe the solution you'd like
A TimeSpanPicker control that binds to a TimeSpan and allows the editing of TimeSpans, including the specification of days (e.g. 15.12:00:00 for 15 and a half days). A TimeSpanPropertyEditor can then be added as the default editor for TimeSpan in a PropertyGrid.

Describe alternatives you've considered
Currently, I am creating a custom editor to achieve the same result and referencing it via an Editor attribute. However, TimeSpan is a common enough CLR type that its omission is strange. A number of other WPF libraries bind their TimePicker equivalents to TimeSpan rather than DateTime for this reason. However having a TimePicker and a new TimeSpanPicker is a reasonable compromise.

Additional context
N/A

Start by examining the existing TimePicker control and PropertyGrid editor integration. Define the scope for a TimeSpanPicker that supports days as well as hours, minutes, and seconds, then determine how a TimeSpanPropertyEditor should become the default editor for TimeSpan. Done means TimeSpan values can be edited and bound through both controls, including values such as 15.12:00:00.