CXX-72 Add compatibility targets for old smoke targets

Make the 'smokeClient', 'smokeCppUnittest', and 'smoke' targets have behavior similar to what they did in the server repo:

- 'smokeCppUnittest' and 'smoke' mean to run the ported tests (since we no longer distinguish between C++ tests and dbtests)
- 'smokeClient' runs the same tests that the old smokeClient runs (basically the targets in client/examples). We can't actually run those unless there is a mongod started on 27999, but that isn't this repo's problem because it doesn't have a way to start/stop such a beast.