Add koan "You can use pattern matching to define [...]"

[s-oram]

Add new koan after discussion in Github issue:
#222 (comment)

[quote]
And, in fact, you can define multiple cases for a function using this sytnax:

lolwat = fn
  "lol" -> "wat"
  _ -> "haha"
end
lolwat.("lol")
# => "wat"
lolwat.("anything")
# => "haha"
lolwat.("rly")
# => "haha"

[/quote]

[felipesere]

Maybe rename “format_reault” to something like inspirational_quote? It would at least sound right for the :ok arm of the function 😅

[s-oram]

@felipesere You're right, that does read better. I've renamed the function. Thanks for reviewing the pull request. Is there anything else? :)

[felipesere]

Yeah, one key thing is keeping CI happy.
If you look under /test you can see tests for all Koans. Essentially we ensure that the right answer (or answers) complete the koan. I’m on my phone this instant but I can give you more hints to later if needed 🤓

[iamvery]

Thanks for contributing! ❤️💙💚💛💜

Just needs answers added to the test suite to keep CI green 🍏

[s-oram]

Thanks guys, I'll take a look at those tests for the CI. :)

[edit] The expected koan result has been added to functions_koans_test.exs.

[felipesere]

Thank you!!!

[s-oram]

Thanks Felipe! :)