plotly#581 adding new test case

Author: monfera

test/image/baselines/gl3d_scatter-line-gradient-2.png

@@ -1,19 +1,17 @@
 {
   "data": [{
-    "x":["-4","-3","-2","-1","0","1","2","3","4","5","6"],
-    "y":["7","5","6","4","2","3","1","3","-1","-4","-2"],
-    "z":["2","3","4","5","4","3","2","1","0","-1","-2"],
-    "mode": "lines+markers",
-    "line": {
-      "width": 5,
-      "color":  [10,15,20,25,30,35,40,45,50,55,60],
-      "colorscale": "Rainbow",
-      "showscale": true
-    },
+    "x":[-4,-3,-2,-1,0,1,2,3,4,5,6],
+    "y":[7,5,6,4,2,3,1,3,-1,-4,-2],
+    "z":[2,3,4,5,4,3,2,1,0,-1,-2],
+    "mode": "markers",
+    "line": {},
     "marker": {
       "size": 10,
       "colorscale": "Viridis",
-      "color": [9,15,20,25,30,35,40,45,50,55,61]
+      "color": [10,15,20,25,30,35,40,45,50,55,60],
+      "cmin": 30,
+      "autocolorscale": true,
+      "reversescale": false
     },
     "name":"Col3",
     "type":"scatter3d",
@@ -23,55 +21,6 @@
     "uid":"3e38e6"
   }],
   "layout": {
-    "yaxis":{
-      "type":"linear",
-      "autorange":true,
-      "rangemode":"normal",
-      "showline":true,
-      "mirror":true,
-      "showgrid":true,
-      "zeroline":false,
-      "zerolinecolor":"rgb(214, 39, 40)"
-    },"xaxis":{
-      "type":"linear",
-      "autorange":true,
-      "rangemode":"normal",
-      "showline":true,
-      "mirror":true,
-      "showgrid":true,
-      "zeroline":false,
-      "zerolinecolor":"rgb(214, 39, 40)"
-    },"scene":{
-      "xaxis":{
-        "type":"linear",
-        "autorange":true,
-        "rangemode":"normal",
-        "showline":true,
-        "mirror":true,
-        "showgrid":true,
-        "zeroline":false,
-        "zerolinecolor":"rgb(214, 39, 40)"
-      },"yaxis":{
-        "type":"linear",
-        "autorange":true,
-        "rangemode":"normal",
-        "showline":true,
-        "mirror":true,
-        "showgrid":true,
-        "zeroline":false,
-        "zerolinecolor":"rgb(214, 39, 40)"
-      },"zaxis":{
-        "type":"linear",
-        "autorange":false,
-        "rangemode":"normal",
-        "showline":true,
-        "mirror":true,
-        "showgrid":true,
-        "zeroline":false,
-        "zerolinecolor":"rgb(214, 39, 40)",
-        "range":[-3,6]
-      }
-    },
     "height":758,
     "width":1310,
     "autosize":true,