testing: track changes to the set of tests
testing: track changes to the set of tests

Use the new SetProperty event to recompute testing.done and testing.ready
every time the set of tests changes.  This removes the need to do so
from the testing-get API, and it will also provide a perfect place to
create PENDING records in the result table.

pvital/patchew,pvital/patchew,pvital/patchew,pvital/patchew