fixed a typo and a declaration

example-script/example-script.qml

@@ -4,7 +4,7 @@ import QtQml 2.0
  * This script is just an example of how to use scripts
  * Visit http://docs.qownnotes.org/ for more information about scripting
  */
-QtObject {
+Script {
     /**
      * Just show some log entries when the script is initialized
      */

external-note-diff/external-note-diff.qml

@@ -37,7 +37,7 @@ Script {
             return;
         }
         
-        // start the diff programm with the selected note paths as parameters
+        // start the diff program with the selected note paths as parameters
         var params = script.selectedNotesPaths();
         script.startDetachedProcess(executablePath, params);
     }