Feature: allow more options on "show events for"

[CampAsAChamp]

Issue that this suggestion fixes

Currently there are only two options for the setting "Show events for" in Preferences > Appearance

• Today
• Today and Tomorrow

I would like to have some other options available which would allow MeetingBar to show events for more days

• 5 days
• 7 days
• 14 days

Solution description

Add additional options to the drop down which would allow MeetingBar to show events for more days

Alternatives considered

Fully customizable number picker, but would probably require a much bigger refactor.

Additional context

I can potentially work on this myself. Never worked in Swift before but after peaking around in the code a bit I see theres a constant for today_n_tomorrow and then theres some switch statements which use that constant and will either fetch the events for 1 day if its set to today or 2 days if set for today_n_tomorrow.

endPeriod = Calendar.current.date(byAdding: .day, value: 2, to: todayMidnight)!

dateTo = Calendar.current.date(byAdding: .day, value: 2, to: dateFrom)!

Hopefully I can just add another constant for five_days and set the value to 5 (same for the other options of 7 days or 14 days)

endPeriod = Calendar.current.date(byAdding: .day, value: 5, to: todayMidnight)!

dateTo = Calendar.current.date(byAdding: .day, value: 5, to: dateFrom)!

[CampAsAChamp]

Is there a way I can build locally without needing an Apple Development Team ID?

If so I'd love to work on this, but looking at CONTRIBUTING.md it looks like I'll need that.