* configure.ac: Check for graphviz and define HAVE_DOT. * lang/qt/doc/Doxyfile.in (HAVE_DOT): Use variable.
* lang/qt/doc/Doxyfile.in: Quiet and no undocumented warnings.
* configure.ac: Look for doxygen if qt is built. Configure new files. * lang/qt/doc/Doxyfile.in: New. * lang/qt/doc/Makefile.am: New. * lang/qt/README: Update. -- Currently this is a standard doxyfile template without much customization.