log-levels: unneeded split_msg stub

[keiravillekode]

The instructions and tests only require 3 functions, so only 3 stubs are needed. The split_msg stub can be removed.

[depial]

Yeah, I remember this being a bit odd when I first completed the exercise. @colinleach What do you think about this?

I would be fine with removing it since it looks like most implementations simply use a single inbuilt split method (making it essentially redundant). That said, I kind of liked having it because it encouraged me to use the more involved implementation of replace composed with split which allowed me to make the message and log_level functions be pure composed functions (i.e. only using ∘ and function names). I'm not sure that's worth making another task, though.

[colinleach]

Careless port from another language, I'm afraid. We don't need split_msg() in Julia, and I'll PR its removal.

There are only 4 community solutions published so far, and of those only @depial's is going to break. This concept comes long before function-composition, so I don't expect many other students will want to use it.

[colinleach]

PR #889

[depial]

PR #889

Resolved with above