add config to separate builtins

[ekohilas]

Without this additional configuration, the rule is too noisy on generally standard behaviour

[KotlinIsland]

thanks for putting the changes in on this

could you give an example of the kind of problematic code?

i think the test you added len already don't require kw args (pow should complain, but i think it's a bug in my impl that doesn't work with overloads)

i think it's probably better to special case the cases where keywords are noisy rather than an entier stdlib blanket. or we just combine it into the default behaviour ( or a config option)?

[KotlinIsland]

#1664 (comment)