more impactful brightness changes

src/Hanglamp.cpp

@@ -38,7 +38,7 @@ void Hanglamp::nextColor(){
   setColor(colorTable[this->colorIndex]);
 }
 
-void Hanglamp::setBrightness(char brightness){
+void Hanglamp::setBrightness(int brightness){
     uint8_t newBrightness = 
     brightness < 0 ? 0 : 
     brightness > 255 ? 255 :

src/Hanglamp.hpp

@@ -9,7 +9,7 @@ class Hanglamp {
     public:
         Hanglamp();
         void setup();
-        void setBrightness(char brightness);
+        void setBrightness(int brightness);
         void adjustBrightness(int add);
         void nextColor();
         void controlsCallback(ControlEvent event);