Breaks are responsive to the calendar

If I finish a meeting early and a break is toggled, it should only be within the limit of my calendar and end before my next scheduled meeting.

Example:

Meeting 1: 11:30-12

Meeting 2: 12-1

If meeting 1 ends at 11:50, the break should only run for 10 minutes. Currently it appears to begin with a 20 minute interval.