[Feature]: Custom error messages to replace stock ones

[ashquarky]

Checked Existing

• I have checked the repository for duplicate issues.

What feature do you want to see added?

Inkay could hook into erreula and replace various system errors with customized ones. The error code itself and the message are potential targets for replacement. Pretendo would need to provide a list of error codes, their replacements, and their messages, as well as translations into all of the Wii U system languages.
If Inkay is aware of errors occuring on the system, this could also potentially be used for analytics in the future to help us quantify error rates and in what games. This might have been useful during the great 101-0502 era. Plus, graphs.

Why do you want to have this feature?

Inform users of:

• Ban reasons
• Unsupported games / games needing Tester accounts
• Maintenance
• Unsupported actions (eShop usage, title update downloads - see Make it so Inkay patches the system menu error message for game updates. #34)

Any other details to share? (OPTIONAL)

Shutter has done some work on this in the past: https://github.com/PretendoNetwork/Inkay/pull/5/files#diff-34d21af3c614ea3cee120df276c9c4ae95053830d7f1d3deaf009a4625409ad2R393

We need to work on what the actual design of this would look like. libcurlwrapper from Aroma would make shutter's design more reasonable now than it was then, but it's still not super flexible to uses other than ban reason. I personally think something based on BOSS would be great, but it's unclear if BOSS can securely deliver personalized files (-> ban reasons!).

Either way, hardcoding errors into Inkay is almost certainly not the answer here, please don't just PR that! It should at least come from a JSON file, which we can then fetch over BOSS or curl or whatever solution we settle on.