change sliderValue() so monitor is correctly updated when inverted slider
change sliderValue() so monitor is correctly updated when inverted slider

mcallegari/qlcplus,peternewman/qlcplus,bjlupo/rcva_qlcplus,peternewman/qlcplus,kripton/qlcplus,joepadmiraal/qlcplus,nedmech/qlcplus,bjlupo/rcva_qlcplus,kripton/qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,peternewman/qlcplus,kripton/qlcplus,plugz/qlcplus,mcallegari/qlcplus,bjlupo/rcva_qlcplus,kripton/qlcplus,peternewman/qlcplus,nedmech/qlcplus,peternewman/qlcplus,bjlupo/rcva_qlcplus,plugz/qlcplus,joepadmiraal/qlcplus,peternewman/qlcplus,joepadmiraal/qlcplus,joepadmiraal/qlcplus,plugz/qlcplus,kripton/qlcplus,kripton/qlcplus,plugz/qlcplus,sbenejam/qlcplus,kripton/qlcplus,plugz/qlcplus,nedmech/qlcplus,mcallegari/qlcplus,bjlupo/rcva_qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,joepadmiraal/qlcplus,bjlupo/rcva_qlcplus,sbenejam/qlcplus,plugz/qlcplus,mcallegari/qlcplus,nedmech/qlcplus,joepadmiraal/qlcplus,nedmech/qlcplus,mcallegari/qlcplus,nedmech/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,plugz/qlcplus,sbenejam/qlcplus