Omitting an lifetime name in the return value of an function should be always forbidden.

[Kimundi]

Right now any function signature of the form

fn foo(...) -> &Bar

is valid, but only if the thing returned has the static lifetime.

I think it would be less confusing if we would just always forbid that, requiring to write out the 'static explicitly in those cases:

fn foo(...) -> &'static Bar

[bluss]

dup of #2478