Long live the TuioTouch input plugin!

This is an import of the tuio2qt plugin (https://github.com/rburchell/tuio2qt),
as of sha 9b1f163ac52ea440e83f16b3906f9b55e21b87be henceforth to be developed as
a part of Qt itself.

This plugin offers touch events via QPA interfaces, using data offered over the
TUIO protocol (http://www.tuio.org).

It is useful for accepting touch input on devices which otherwise don't have
touch input (such as desktops) for the purposes of development, as well as
accepting input from some hardware which offers up touch events specifically
over the TUIO protocol.

Known "shortcomings" at this time, as documented in the README:
 * Multiple TUIO sources sending data at the same time will conflict. This will
   not cause problems, strictly speaking, but it will not work well (repeated
   touchpoint release/press events for the same IDs)
 * TCP transport is not currently supported. I don't see a need for it at this
   time, but I have left the capability in terms of port acceptance open for it
   to be made available.

Change-Id: I7178f9db13c635268db8460fbe4d4ea6be654c05
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>