Finish new timetable UI

[riccardocalligaro]

For now the current missing features / issues are present:

• doesn't do anything when clicked
• same color for every cell
• reduce font size and minor text adjustments
• test it and better divide the code

need to:

• implement subject color in database to assign to every subject so in the start screen the card lesson are of the same color of the subject

[riccardocalligaro]

Implemented in d327a5b00f1a10b4d22db6ae5041b13475eed2f9