Makes the code more general and not directly tied to specifically
TCP sockets.

Handle the clipboard directly in the server, avoiding the
dependency on vncconfig. This commit adds support for clipboard
from the client to the server. Handling of the other direction
will follow.

It is easier to control object life time and avoid magical socket
duplication by having a single TcpListener object to pass around.
We have to be more careful about deleting the object though.

Patch by Jay Kulpinski. Prevents -inetd mode from automatically
finding a free X11 display number.

The TcpListener constructor now takes a 'struct sockaddr*' instead of
a string, and the createTcpListeners function creates TcpListener
instances for an address based on the results from getaddrinfo().

The XserverDesktop class now takes a list of TcpListener instances for
each of the RFB and HTTP sockets.

The TcpListener::closeFd member variable is not used and has been
removed.

On some platforms va_list might be defined as something that causes
ambiguity and results in the wrong function being called.

The internal Xorg headers are very incompatible with C++ and we've had
to resort to all kinds of hacks in order to include them in our C++
code. This approach isn't really viable long term so restructure things
so that we have a glue layer written in C that bridges the Xorg core
with the RFB classes.