Implemented simple save button

editor/editor.php

@@ -14,6 +14,7 @@
             <ul id="selected-targets"></ul>
         </section>
     </section>
+    <button id="save" type="submit" class="primary">Save and publish</button>
     <section>
         <h3>Collected items</h3>
         <ul id="selected-items"></ul>

editor/js/interactions.js

 import jQuery from "jquery";
-import { state } from "./editor";
+import { state, graph } from "./editor";
+import { saveGraphJson } from "../../datasets/datasets";
 
 /**
  * Initiates all the handlers for button presses and input changes.
@@ -8,4 +9,7 @@ export function initInteractions() {
     jQuery("button#clear-collection").on("click", () => {
         state.clearSelectedItems();
     });
+    jQuery("button#save").on("click", () => {
+        saveGraphJson(space_id, graph.getCleanData());    // space_id defined globaly through knowledge-space.php
+    });
 }