Add common/sha1.h and common/sha1.c so that we have the SHA routines
even if openssl is not available. From the IETF SHA RFC example code.

Remove the UTF-8 encoding hack. This was really just an experiment.

If the protocol passed in the handshake has "binary" then don't base64
encode for the HyBi protocol. This will allow noVNC to request the
binary data be passed raw and not base64 encoded. Unfortunately, the
client doesn't speak first in VNC protocol (bad original design). If
it did then we could determine whether to base64 encode or not based
on the first HyBi frame from the client and whether the binary bit is
set or not. Oh well.

Misc Cleanup:

- Always free response and buf in handshake routine.

- Remove some unused variables.