Add colour/unicode/emojis to `cabal check`

[ffaf1]

From this good suggestion.

@ffaf1 for the record, i think Cabal's messaging is severely under-developed in terms of decorations. Please, give me more emojis and alike! One of the ways to figure how to do it is to steal from someone, i think. E.g. cargo would be my first choice to look for an example. I guess, I could look into what Julia and its package manager do in such cases. I just need to figure out what would be the closest scenario…

A good article on accessibility considerations here.

[andreabedini]

I am not against experimenting with empjis but I would start from adding colours first.

If we start displaying info/warn/error messages in different colours, mistakes in this categorisation would become more obvious; and fixing those miscategorisation would improve everybody's experience, whether they see the colours or not.

Just my 2c ☺️

[ulysses4ever]

Yeah, I didn't mean emoji literally, tbh. More like 1) Unicode niceties in general, and 2) Colors.

[jneira]

please, take in mind fallback to simle shells without color or unicode support