Specifications of bool opeartor==(path, string) is changed.

[Shuji Yamasaki <shu@…>]

Before:
path("c:\\file") == "c:\\file" //true
path("c:\\file") == "c:/file" //true

Current:
path("c:\\file") == "c:\\file" //false
path("c:\\file") == "c:/file" //true

I found the comment in path.hpp:
//  operator == uses string compare rather than !(lhs < rhs) && !(rhs < lhs) because
//  the result is the same yet the direct string compare is much more efficient that
//  lexicographical_compare, and lexicographical_compare used twice at that.

Is it intended?

[Beman Dawes]

(In [56139]) Fix #3385, add test cases