Add libraries
Add asynchronous timetable loader, not works well

Correct example is in MainActivity.
The key point is "Do not use AsyncTask.get() before onPostExecute()."
If you call get(), the UI thread blocks and dialog is not shown up.
Instead, you should use result in onPostExecute()
or self-created callback function.
Refactor codes: CHange class name, implement mock precisely
Delete unused LinearLayout node