Merge pull request #71 from plotly/test-pie-opacity

modify pie color test to cover opacity

Author: alexcjohnson

test/image/baselines/pie_labels_colors_text.png

@@ -17,7 +17,7 @@
       ],
       "marker": {
         "colors": [
-          "red",
+          "rgba(255,0,0,0.5)",
           "orange",
           "blue",
           "yellow",