Custom version requested by rlbierb.

See http://lalescu.ro/liviu/fet/forum/index.php?topic=86.msg12852#msg12852

In short: However this year we want to add more flexibility to have some classes that are two hours in duration with two days between, and other
classes one daily but at the same time each day.  I was thinking maybe there could be a button on the activity page that allowed one to quickly
add the constraint "same time each day" for each subactivity if the split was greater than 1.

The feature is in the Advanced menu or in Time/Advanced shortcut button.