M300 presetPenFeedrate bug, document corrections

SphereBot.ino

@@ -1092,7 +1092,7 @@ void processCommand()
 
         if (mzActiveMode == M)
         {
-          if (GCode.HasWord('F'))
+          if (GCode.HasWord('F') && presetPenFeedrate <= 0)
           {
             penFeedrate = GCode.GetWordValue('F');
           }
@@ -1198,7 +1198,7 @@ void processCommand()
         }
         break;
 
-      // M308 - Sets the M300 pen up preset value.
+      // M308 - Sets the M300 pen up preset threshold value.
       // S values less than the value move the pen down.
       case 308:
         if (GCode.HasWord('P'))
@@ -1310,14 +1310,14 @@ void processCommand()
 
         print("M308 P");
         print(mAdjustPreset);
-        print(" ;M308 Pxxx - M Adjust Preset: ");
+        print(" ;M308 Pxxx - M Adjust Preset Threshold: ");
         print(mAdjustPreset);
         print("  M Adjust Calculated: ");
         println(mAdjustCalculated);
 
         print("M309 P");
         print(zAdjustPreset);
-        print(" ;M309 Pxxx - Z Adjust Preset: ");
+        print(" ;M309 Pxxx - Z Adjust Preset Threshold: ");
         print(zAdjustPreset);
         print("  Z Adjust Calculated: ");
         println(zAdjustCalculated);