docs(graph3d): Adjusted graph3d doc for autoscaling; ref Issue #2540 (#2812)

* Adjusted doc for autoscaling; ref Issue #2540

* Edited Defaults column for Min/Max options for completeness

docs/graph3d/index.html

@@ -547,14 +547,18 @@ var options = {
     <tr>
       <td>xMax</td>
       <td>number</td>
-      <td>none</td>
-      <td>The maximum value for the x-axis.</td>
+      <td>from data</td>
+      <td>The maximum value for the x-axis.
+         If not set, the largest value for x in the data set is used.
+      </td>
     </tr>
     <tr>
       <td>xMin</td>
       <td>number</td>
-      <td>none</td>
-      <td>The minimum value for the x-axis.</td>
+      <td>from data</td>
+      <td>The minimum value for the x-axis.
+         If not set, the smallest value for x in the data set is used.
+      </td>
     </tr>
     <tr>
       <td>xStep</td>
@@ -590,14 +594,18 @@ var options = {
     <tr>
       <td>yMax</td>
       <td>number</td>
-      <td>none</td>
-      <td>The maximum value for the y-axis.</td>
+      <td>from data</td>
+      <td>The maximum value for the y-axis.
+         If not set, the largest value for y in the data set is used.
+      </td>
     </tr>
     <tr>
       <td>yMin</td>
       <td>number</td>
-      <td>none</td>
-      <td>The minimum value for the y-axis.</td>
+      <td>from data</td>
+      <td>The minimum value for the y-axis.
+         If not set, the smallest value for y in the data set is used.
+      </td>
     </tr>
     <tr>
       <td>yStep</td>
@@ -615,16 +623,20 @@ var options = {
     </tr>
 
     <tr>
-      <td>zMin</td>
+      <td>zMax</td>
       <td>number</td>
-      <td>none</td>
-      <td>The minimum value for the z-axis.</td>
+      <td>from data</td>
+      <td>The maximum value for the z-axis.
+         If not set, the largest value for z in the data set is used.
+      </td>
     </tr>
     <tr>
-      <td>zMax</td>
+      <td>zMin</td>
       <td>number</td>
-      <td>none</td>
-      <td>The maximum value for the z-axis.</td>
+      <td>from data</td>
+      <td>The minimum value for the z-axis.
+         If not set, the smallest value for z in the data set is used.
+      </td>
     </tr>
     <tr>
       <td>zStep</td>