cppreference.com: fix [static], [virtual]

[glenvt18]

Cut [static] or [virtual] and prepend it to the tail.

Examples to reproduce: https://en.cppreference.com/w/cpp/error/exception what [virtual]

cppman 'std::exception'

https://en.cppreference.com/w/cpp/string/basic_string npos [static]

cppman 'std::basic_string'

[aitjcize]

lgtm, thanks!