point out the blanket impl of Parser

[lolbinarycat]

https://docs.rs/nom/latest/nom/trait.Parser.html#impl-Parser%3CI%3E-for-F

this trait impl here is important to making sense of version 8 of the library, and I think it would make sense to draw attention to it, probably in the Making new parsers with function combinators section.

[Atreyagaurav]

I second this. I am trying to use v8.0 and am completely lost while trying to use slice of custom types to make parser combinators, v7.1 allowed it by using the functions, but the trait system in v8.0 is making me hit a lot of "Can't implement this trait for foreign types", and such problems so good examples and doc would help.