Add logging tests

[icanzilb]

Now that the basic functionality proves to be working it's time to add tests.

Ideas:

• the os framework is most likely Obj-C, let's swizzle OSLog and have a bunch of tests verify what's being logged.
• other ideas?

[icanzilb]

In an ideal world, we'll have a separate test suite with integration tests that pulls TimelaneCombine and builds it with the Core from the current PR - to verify that framework settings or some such don't break dependencies

[icanzilb]

Stale