Testing framework

[ldelelis]

There's a bunch of critical functionality that's not apparent at first sight. We should define the expected behaviour for the kernel's "boot": module discovery, load, error handling, maybe logging?

[ldelelis]

Adding to the intent of the issue: how should we handle module testing? Should it be handled with the core's tests, or should whichever modules that need testing be turned into complex modules, with a tests directory?