TAU Improved Lectures

Add a download button to video playback screens, a slider for controlling the playback speed, and free text search for searching for courses. This way you can find lectures easily, view them offline, or even skip downloading them if the purpose of the download was to change the speed. Also added a search bar to the main page to make it not super annoying to find courses. Happy viewing! Teaching icons created by Eucalyp - Flaticon - https://www.flaticon.com/free-icons/teaching Icons created by surang - Flaticon - https://www.flaticon.com/free-icons/teach