Save modal component for explore v2 (#1612)

* Added specs for SaveModal

* Move datasource_id and datasource_name to form_data

* Add comments

* Deleted redundant fetchDashboard

* Replcae has_key for python3

* More react and less jquery

* Added alert for save slice

* Small changes based on comments

* Use react bootstrap

superset/assets/javascripts/explorev2/components/FieldSet.jsx

@@ -14,7 +14,11 @@ const propTypes = {
   places: PropTypes.number,
   validators: PropTypes.any,
   onChange: React.PropTypes.func,
-  value: PropTypes.oneOfType([PropTypes.string, PropTypes.bool, PropTypes.array]).isRequired,
+  value: PropTypes.oneOfType([
+    PropTypes.string,
+    PropTypes.number,
+    PropTypes.bool,
+    PropTypes.array]).isRequired,
 };
 
 const defaultProps = {