[explore] convert query and save btns to react (#690)

* start to convert query and save btns to react

* more explore.jsx to explore/

caravel/assets/javascripts/explore/components/QueryAndSaveBtns.jsx

@@ -0,0 +1,33 @@
+import React, { PropTypes } from 'react';
+import classnames from 'classnames';
+
+const propTypes = {
+  canAdd: PropTypes.string.isRequired,
+  onQuery: PropTypes.func.isRequired,
+};
+
+export default class QueryAndSaveBtns extends React.Component {
+  render() {
+    const saveClasses = classnames('btn btn-default', {
+      'disabled disabledButton': this.props.canAdd !== 'True',
+    });
+
+    return (
+      <div className="btn-group query-and-save">
+        <button type="button" className="btn btn-primary" onClick={this.props.onQuery}>
+          <i className="fa fa-bolt"></i>Query
+        </button>
+        <button type="button"
+                className={saveClasses}
+                onClick={this.props.onSave}
+                data-target="#save_modal"
+                data-toggle="modal"
+        >
+          <i className="fa fa-plus-circle"></i>Save as
+        </button>
+      </div>
+    );
+  }
+}
+
+QueryAndSaveBtns.propTypes = propTypes;