include: uv_udp_recv_cb now takes const uv_buf_t*
include: uv_udp_bind{6} now takes sockaddr_in*
include: uv_udp_send{6} now takes sockaddr_in*
include: make uv_write{2} const correct
windows: fix flags assignment in uv_fs_readdir()
windows: fix mingw swprintf() usage
windows: fix stray comments
windows: remove unused variable in tty.c
windows: remove unused is_path_dir() function