message: Add missing Qt library includes
  Add checks for WebEngineWidgets and WebChannel
diff: @@ -88,7 +88,7 @@ if test "x$enable_gui" = "xyes" ; then
  AC_SUBST([LRELEASE])
  AC_MSG_NOTICE([Using Qt5 at $with_qt5])
  ], [
  - PKG_CHECK_MODULES(QT5, [Qt5Core Qt5Gui Qt5Widgets Qt5Network], [AC_MSG_NOTICE([Found Qt5 using pkg-config.])], [
  + PKG_CHECK_MODULES(QT5, [Qt5Core Qt5Gui Qt5Widgets Qt5Network Qt5WebEngineWidgets Qt5WebChannel], [AC_MSG_NOTICE([Found Qt5 using pkg-config.])], [
  PKG_CHECK_MODULES(QT5, [QtCore >= 5 QtGui >= 5 QtWidgets >= 5 QtNetwork >= 5 QtWebEngineWidgets >= 5 QtWebChannel >= 5], [AC_MSG_NOTICE([Found Qt >= 5 using pkg-config.])], [
  AC_MSG_ERROR([Qt5 not found.])
  ])
  