Code that is duplicated in the backends moved to
io.sockets.secure.openssl. The wait-for-fd verb used by do-ssl-accept
doesn't have any equivalent on Windows so that needs to be
implemented.
Unified the drain and refill generics and put their definition in
io.files. They are now used by both the windows and unix ssl backend
for io. Windows ssl kind of works now, but the error cases are not
implemented correctly.
Björn Lindqvist