Added visualization of current unit tests running.

Moved unit tests to their own thread (so you can do whatever while unit testing)
Now all errors in unit testing are logged in the unit testing window console.
Now downloads unit tests that need to be downloaded.
When waiting for background tasks to complete, the number of queued tasks is now shown.
Optimized thread cpu usage
Made background thread (and unit test thread) only run when there are tasks for it.
Organized TodoList (and made it into a html file)
    Only kept features that don't need to be prioritized on the todolist (and renamed it accordingly)
    TodoList.html is now organized neatly.