Create a toolbarReady hook for attaching toolbar tools

Using an event introduces a race condition where the extension
adding the listener has to do so before WikiEditor finishes loading.

Change-Id: I5a8dc6f8fd1b1939b5d98307b20ef1fd355cee99

extension.json

@@ -1,6 +1,6 @@
 {
 	"name": "WikiEditor",
-	"version": "0.5.2",
+	"version": "0.5.3",
 	"author": [
 		"Derk-Jan Hartman",
 		"Trevor Parscal",

modules/jquery.wikiEditor.toolbar.js

@@ -768,6 +768,8 @@
 				}
 				setTimeout( function () {
 					context.$textarea.trigger( 'wikiEditor-toolbar-doneInitialSections' );
+					// Use hook for attaching new toolbar tools to avoid race conditions
+					mw.hook( 'wikiEditor.toolbarReady' ).fire( context.$textarea );
 				} );
 			}
 		}