use video scaling instead of NPB luminance & new ABL (#4798)

* updated color scaling to preserve hue at low brightness resulting in much better colors
* replace NPBlg with NPB, moved brightness scaling to bus manager
* improved gamma table calculation: fixed mismatch in inverting gamma table calculation: inversion should now be as good as it gets
* code cleanup, fixed gamma being applied in unnecessary places

Improvements to ABL handling:
- removed strip level handling, ist now all done on bus level
- limiter now respects pixel mapping
- proper handling of white channel
- improved current estimation
- current is now always correctly reported to UI
- minimal FPS impact if the ABL is not limiting but slighly higher impact for global ABL limit due to double-scaling

- moved brightness scaling to BusDigital
- created new header file colors.h to be able to access color functions in bus-manager.
- updated colo_fade() with better video scaling to preserve hue's at low brightness
- added IRAM_ATTR to color_fade (negligible speed impact when compared to inline and benefits other functions)
- added IRAM_ATTR to color_blend as it is used a lot throughout the code, did not test speed impact but adding it to color_fade made it almost on-par with an inlined function

Additional changes:
- fixes for properly handling `scaledBri()` (by @blazoncek)
- also use bit-shift instead of division in blending for ESP8266
- improvements for faster "softlight" calculation in blending
- changed some variables to uint8_t to maybe let the compiler optimize better, uint8_t can be faster if read, store and set are all done in uint8_t, which is the case in the ones I changed
- various minor code formatting changes

wled00/udp.cpp

@@ -424,7 +424,7 @@ void realtimeLock(uint32_t timeoutMs, byte md)
     }
     // if strip is off (bri==0) and not already in RTM
     if (briT == 0) {
-      strip.setBrightness(scaledBri(briLast), true);
+      strip.setBrightness(briLast, true);
     }
   }
 
@@ -434,14 +434,14 @@ void realtimeLock(uint32_t timeoutMs, byte md)
   realtimeMode = md;
 
   if (realtimeOverride) return;
-  if (arlsForceMaxBri) strip.setBrightness(scaledBri(255), true);
+  if (arlsForceMaxBri) strip.setBrightness(255, true);
   if (briT > 0 && md == REALTIME_MODE_GENERIC) strip.show();
 }
 
 void exitRealtime() {
   if (!realtimeMode) return;
   if (realtimeOverride == REALTIME_OVERRIDE_ONCE) realtimeOverride = REALTIME_OVERRIDE_NONE;
-  strip.setBrightness(scaledBri(bri), true);
+  strip.setBrightness(bri, true);
   realtimeTimeout = 0; // cancel realtime mode immediately
   realtimeMode = REALTIME_MODE_INACTIVE; // inform UI immediately
   realtimeIP[0] = 0;