nucleotide-codons: deprecate in favour of protein-translation

[petertseng]

Closes #268

[ErikSchierboom]

If I look at other deprecated exercises, they almost all start with "NOTE: This exercise has been deprecated.". I like that this is the first thing you see in that case, which makes it really clear that the exercise is deprecated. Perhaps we can do that here too?

[petertseng]

Let's try that, then. Since you didn't object to linking the issue nor the suggestion of what exercise to implement instead, I kept them, of course, just added the necessary line

[petertseng]

Someone needs to remind me what this .deprecated file does again, whether this PR needs to be dependent on exercism/rust#258.

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Okay far as I can tell from exercism/DEPRECATED.x-api#140 , deprecating it globally just prevents it from showing up in the "to be implemented" section of any other track, so I don't think exercism/rust#258 and this PR need to be temporally dependent on each other in some way.

[ErikSchierboom]

I think linking to the issue and the suggestion are great features, so I'm glad you kept them in.

That means this PR can be merged, right?

[petertseng]

That means this PR can be merged, right?

I'm ready for it to happen, and I think it is safe even while the Rust PR hasn't been merged. If we are unsure at all, we better let @kytrinyx know before the daily site deploy, in case it does cause any unexpected effects.

[ErikSchierboom]

@kytrinyx would merging this PR would be safe to do?

[kytrinyx]

Yes, this is safe to merge.