- Supports 'scheduled' date for tasks, which represent the earliest opportunity
to work on a task.
- Added unit tests for urgency.
- Implemented color rule.
- Added scheduled to 'info' report.
- Updated assorted documentation.
- Removed comments in default rc because they are never seen.
- Added (broken) 'ready' report, which is like 'next' but only for ready tasks.
- Corrected all unit tests that used the old syntax "task done 1" to
use the new syntax "task 1 done". Similarly, "task 1 ..." is now
"task 1 modify ...".