Calendar: Hide Overview Button But Days = 1

[huydocs19]

• Hide overview button if the event is 1 day
• Make the overview "width" 2 or 3 days for events < 4 days.
• Issue Link: https://github.com/snap-cloud/snapcon/issues/215

[cycomachead]

I am finally getting around to merging all of your work! Thanks so much!