(close_fd_array): Use template argument deduction to find array length. (close_fd): New helper to close single file descriptors.
(close_fd_array): Use template argument deduction to find array length.
(close_fd): New helper to close single file descriptors.

zmij/pg_async,zmij/tip-http,zmij/tip-http,zmij/tip-http,zmij/tip-http