Rename Error-mode to Default-mode in utility-functions

source/DeviceMode.m

@@ -35,7 +35,7 @@ function mode = DeviceMode(type, modeNo)
             case DeviceType.InfraRed
                 mode = DeviceMode.InfraRed(modeNo);
             otherwise
-                mode = DeviceMode.Error(0); % Need to think about this...
+                mode = DeviceMode.Default.Undefined; % Need to think about this...
         end
     catch 
         error('MATLAB:RWTHMindstormsEV3:noclass:DeviceMode:invalidInputValue',...

source/isModeValid.m

@@ -2,7 +2,7 @@ function isValid = isModeValid(mode, type)
 % Returns whether given mode is a valid mode in given type.
     isValid = true;
     
-    if strcmp(class(mode), 'DeviceMode.Error')
+    if strcmp(class(mode), 'DeviceMode.Default')
         return;
     end