Include modules in solutions

[vdauwera]

Per slack convo about the new linting checks:

Phil
Basically all of the errors are due to missing module include statements. I'm not sure why the solutions don't always have all of the module files that they need to include - is this intentional @Geraldine (GG)? For example, solutions/5-hello-containers/modules only has cowpy and doesn't include sayHello, convertToUpper etc from the previous 4-hello-modules.

Geraldine (GG)
It’s because the solutions contain only the files that the student had to modify, and there are multiple places where the modules were already written earlier
So we don’t repeat the files that are unchanged
We could include the module files if you think it’s worth the duplication

Phil
Yeah I think so, it's the only way that the code will parse (-> run, or lint / format)
I think it's nice if the solutions work out of the box? Though I appreciate that this means duplication