Added carousel functionality to week-only format

[lucasvienna]

I used the same existing implementation and merged most of the code necessary to handle both the monthly and weekly view. I managed to removed a lot of duplicate code doing this, but I believe the builder methods can also be merged in a future version.

[hyochan]

Thanks. It really looks great. But when changing weekFormat from hot reloading it throws error like below because the widget wasn't constructed.

I think both should be constructed to prevent throw. What do you think?

[lucasvienna]

Oh, I see what you mean. Yeah, that might cause problems when switching modes during runtime. I will push an update tomorrow with a fix.

[lucasvienna]

Fix pushed, you can try it out again :)

[hyochan]

Fantastic!