Add `resultTime` field to `T.T.Core.Result`.

`resultTime` is initialized to 0 by default, and then overriden with the
actual test time by `executeTest`.

`TestReporter`s reporter is modified to return a continuation that
accepts the runtime of the entire suite before finishing.
add timing info to the ConsoleReporter's output.
Add the Time type synonym and some documentation
Do not print timings when they are insignificant
Versioning is no longer monotonic across packages
Release 0.10