update schema

Author: emilykl

test/plot-schema.json

@@ -280,7 +280,7 @@
     },
     "plotlyServerURL": {
       "description": "Sets the URL for the `sendChartToCloud` modebar button. When clicked, the button will send the chart data to this URL.",
-      "dflt": "",
+      "dflt": "https://cloud.plotly.com/newchart",
       "valType": "string"
     },
     "queueLength": {
@@ -342,7 +342,7 @@
     },
     "showSendToCloud": {
       "description": "Should we include a modebar button that sends this chart to a URL specified by `plotlyServerURL`, for sharing the chart with others? Note that this button will (after a confirmation step) send chart data to an external server.",
-      "dflt": false,
+      "dflt": true,
       "valType": "boolean"
     },
     "showSources": {