Remove Misc.may_map and similar

[lpw25]

Now that we have an Option module in the stdlib we can remove some helper functions from the compiler. I grepped for matches on Some to try to find all the clones of Option.map and Option.iter so hopefully I got them all.

[trefis]

Good to go when CI's green.

[gasche]

Looks good to me. I think this is fine to merge once the CI agrees.

Most of the changes are obviously readability-preserving -- I would say that the new names are better than the old one. The use of Option.fold instead of value_default required a bit more thinking: from a callsite perspective it replaces a not-very-clear API by another not-very-clear API, because this thing is simply a bit weird. Maybe we should have an Option.for_all function (and Option.exists I guess), which would have made the use-cases clearer.

[lpw25]

Maybe we should have an Option.for_all function (and Option.exists I guess), which would have made the use-cases clearer.

Yeah, Option.for_all would make those cases clearer. At least we are now implementing a for_all with a fold which is more obviously correct.

[gasche]

check-typo results:

./lambda/translcore.ml:651.81: [long-line] line is over 80 columns
./typing/tast_mapper.ml:215.81: [long-line] line is over 80 columns
./typing/typecore.ml:527.81: [long-line] line is over 80 columns

[lpw25]

check-typos fixed and Changes entry added