Fix of the explore action button bug without reload

[prokh]

*Solves #1189: Download button, share button, and url shortener button stay not in sync with visualization while editing
*Syncs the data from the server response to the data in slice.
*Calls a callback to rerender buttons when data changes.

Current Situation:

• slice.data is the bootstraped data and is never changed. It contains the initial form data.
• slice.jsonEndpoint() calculates the json endpoint from the form, referenced by #("query").
• When the user changes the form, even when he hits query, slice.data.json_endpoint is inconsistent with the form data and slice.jsonEndpoint().
• The slice is passed to the React components for the json/csv/embedd. Currently, they access slice.data.json_endpoint/csv_endpoint/standalone_endpoint. Thus they are inconsistent.

There are two options:

1. Replace in the React components slice.data.json_enpoint by slice.jsonEndpoint() and add a analogous function for csv. The former calculates the the json endpoint from the form data.
   Problem: If the user changes the form but has not updated the chart, the chart and the json data is inconsistent.
2. Update slice.data.json_endpoint/csv_endpoint in slice.done() with the data from the server. Then rerender the React components (,which is the recommened way when the props change (setProps is deprecated)). The json/csv endpoints are consistent with the visualization.

The second option in implemented. We only update slice.data.json_endpoint/csv.endpoint/form_data/standalone_endpoint. slice.data.token/viz_name might get inconsistent.