docs show different method definitions for core and std

[lucidd]

I noticed that the docs on Iterator differ depending on if you look a core::iter::Iterator or std::iter::Iterator. In the std version the declaration of the lifetime 'r in the methods is missing.
Im not sure if this is a bug or intended but its confusing if you look at the std version and wonder where lifetime 'r comes from.

[reem]

@lucidd Your links are swapped.

[lucidd]

@reem thanks changed it.

[steveklabnik]

This is a bug and we have an open issue, or so I thought, but I can't find it.

[lucidd]

@steveklabnik i think i found it #14462 so closing this as a duplicate