Initial commit of Qt 4 sources

Backported from nethack-i18n (http://sourceforge.net/projects/nethack-i18n/).
Qt-specific files from the previous nethack-qt

These files are carried forward from nethack_3.4.3-12.debian.tar.xz, the last
Debian NetHack to support Qt 3, and modified from those files in the same way
that the corresponding nethack-x11 files were modified.
Add a patch to add the Qt 4 code to the tree
Add rules for nethack-qt target

In addition to rules corresponding to those for the other packages, this adds
the LINK variable for all packages.  The Qt interface needs to be linked with
g++ instead of cc or gcc.  The make file (sys/unix/Makefile.src) already uses
this variable, and did not need to be modified.
Add description for nethack-qt package

Also, dependency on libqt4-dev.
Change log entry, and distinct version.