qt-tools: add qi_generate_qt_conf

Change-Id: I87aa1ac63e5ca7fcd567f0a46bc81e56f10429dc

Conflicts:
	cmake/qibuild/modules/qt-tools.cmake
qt-tools: prefer qt4

Change-Id: I13b65a01374a715bae04e5b05c407687d38f2638
Reviewed-on: http://gerrit.aldebaran.lan/43025
Tested-by: gerrit
Reviewed-by: dmerejkowsky <dmerejkowsky@aldebaran-robotics.com>

Conflicts:
	cmake/qibuild/modules/qt-tools.cmake
qibuild v3.5.3

Change-Id: I4b80dd78ddb977f392900608e677f25f72010012