* Enable unittest.suite to accept partial calls of rules
This permits using `unittest.suite` with test rules that have nondefault
attributes, while retaining compatibility with current usage.
For instance, this permits setting a `timeout` on each test in a
`unittest.suite`. Previously, all tests in a `unittest.suite` would
have the default timeout, with no good way to alter this. This
made it hard to eliminate all the warnings produced from using the
`--test_verbose_timeout_warnings` bazel option.
While timeouts were the motivation, the solution here is not specific
to timeouts. It will permit arbitrary additional arguments to the test
rules in a `unittest.suite`.
Fixes #98
* Respond to review feedback.
* Document a breaking change in bazel that this code needs to be aware of.
David Sanderson