split doubles court time

There should be the ability to decide how much time a reservation type costs. E.g., doubles cost 0.5 unit of time each hour instead of 1.

Here is an example of the issue, 
you have 4 players, A, B, C, D. And they want to play doubles...

If they book a court for doubles, after the 2 hours, each player will have spent 2 hours each.
But if they book 2 singles sessions, the first hour with A and B, second hour with C and D. They technically get 2 hours of court time, but each player only spends 1 hour.

This is clearly a bug / exploit that should be fixed. Doubles should be split across the 4 players so after 2 hours of doubles, each player incurs 1 hour of time used.

These are valid bookings so I do not think we should tell players not to exploit it. It's also hard to enforce. This is a problem on the platform that should be addressed.