Add "Only keep last [X] days of messages" option to speed BB up on older phones

[Perifractic]

Hey Zach and the team, I'm still using your amazing app daily when out with family, on my modern Kyocera KY-42C flipphone (Zach has one!).

I am running into one problem. It seems the more messages I get, the more starting it slows down. It is now taking about 60 seconds to open, and is becoming unusable due to that. Clear data fixes temporarily, until messages sync again.

I'm enquiring therefore if you could add an option that I've seen on some other clients: "Only keep messages from the last [X] days"? I would set this to 7, and it would greatly speed up the app - I'm sure of it.

Thank you in advance and keep up the great work.