Change type of LuminosityPercentage to int from byte (#36)

The LuminosityPercentage stayed at 0 when initializing the screen.

Co-authored-by: Michiel Ryvers <michiel.ryvers@sbb.be>

Author: demichiel

nanoFramework.M5StickCommon/Screen.cs

@@ -19,7 +19,7 @@ public class Screen : ScreenBase
         private const int DataCommand = 23;
         private const int Reset = 18;
         private static Axp192 _power;
-        private static byte _lumi;
+        private static int _lumi;
         private static bool _isInitialized = false;
 
         /// <summary>
@@ -53,7 +53,7 @@ public Screen()
         /// <summary>
         /// Enables or disables the screen.
         /// </summary>
-        public static new bool Enabled
+        public new static bool Enabled
         {
             get => IsEnabled;
 
@@ -68,16 +68,16 @@ public Screen()
         /// Sets or gets the screen luminosity.
         /// </summary>
         /// <remarks> On M5Stick, anything less than 20% will be fully black</remarks>
-        public static new byte LuminosityPercentage
+        public new static int LuminosityPercentage
         {
             get => _lumi;
 
             set
             {
                 // For M5Stick, values from 8 to 12 are working fine
                 // 2.5 V = dark, 3.0 V full luminosity
-                _lumi = (byte)(value > 100 ? 100 : _lumi);
-                _power.LDO3OutputVoltage = ElectricPotential.FromVolts((byte)(_lumi * 0.5 / 100.0 + 2.5));
+                _lumi = value > 100 ? 100 : value;
+                _power.LDO3OutputVoltage = ElectricPotential.FromVolts(_lumi * 0.5 / 100.0 + 2.5);
             }
         }
     }