restore MM functionality to not reset segments if 2D settings change!!!

customeffects.js:
- rename downloadCEFile to downloadGHFile
- downloadGHFile: add GH ledmaps folder

FX_fcn.cpp and set.cpp:
- change makeAutoSegments with resetSegments(true)

wled00/FX_fcn.cpp

@@ -2097,7 +2097,7 @@ bool WS2812FX::deserializeMap(uint8_t n) {
       Segment::maxWidth = p.width;
       Segment::maxHeight = p.height;
 
-      makeAutoSegments();
+      resetSegments(true); //WLEDMM not makeAutoSegments() as we only want to change bounds
     }
 
     customMappingSize  = map.size();

wled00/data/index.js

@@ -1377,6 +1377,7 @@ function drawSegmentView() {
 			post();
 		}, function(error) { //error handling
 			console.log(error);
+			// downloadGHFile("LM", fileName, true, false); WLEDMM: remove as this has too much impact
 			post();
 		});
 	}

wled00/set.cpp

@@ -726,7 +726,7 @@ void handleSettingsSet(AsyncWebServerRequest *request, byte subPage)
         strip.panel.push_back(p);
       }
       strip.setUpMatrix(); // will check limits
-      strip.makeAutoSegments(true);
+      strip.resetSegments(true);  //WLEDMM not makeAutoSegments(true) as we only want to change bounds
       strip.deserializeMap();
     } else {
       Segment::maxWidth  = strip.getLengthTotal();