workaround for unicorn 5.3.0
unicorn 5.3.0 introduced a new Unicorn::TCPSrv and
Unicorn::TCPClient constants to distinguish TCP sockets
from Unix ones from its check_client_connection feature.
These classes screw up our direct inheritance of Kgio::Socket
from the Rainbows::Client class. Since we do not support
check_client_connection, we do not need these new classes in
unicorn. Removing Unicorn::TCPSrv and aliasing it as
Kgio::TCPServer is sufficient for now. In the future,
removing all kgio dependencies from Rainbows! will be prioritized.
Thanks to Claudio Poli for reporting the bug:
https://bogomips.org/rainbows-public/
9267B33C-D13C-47E1-8892-
4777B96DDCD1@gmail.com/