Display alternate time units for roll-up tasks

Currently any Roll-up task that is aggregating the time from its subtopics will display the duration or effort in workdays. The non-roll-up subtopics may display times in minutes, hours, days, weeks, etc.

As a user, I'd like the units of time displayed for a Topic in Map View that is considered a Roll up Task to display the summary information for Task Info (Effort and Duration) in one of the following ways:

1. Automatically use the timescale (minutes, hours, …, months) of the non- Rolled up Tasks beneath it.
2. Provide configurable thresholds so that Roll up Tasks can automatically adjust their timescales (if hours > 48, then switch to days; if days > 7 then switch to weeks, etc.)
3. Allow users to manually set the timescales for individual Roll up Tasks and provide a default setting (in the theme perhaps) of the user’s preference for newly created roll up topics.