Fix obscure error on invalid reminder.
Fix obscure error on invalid reminder.

If the data in the reminder isn't valid, detect that instead of trying
to pass nil to several different functions.

Signed-off-by: brian m. carlson <738bdd359be778fee9f0fc4e2934ad72f436ceda@crustytoothpaste.net>

bk2204/daniel-ruby,bk2204/daniel-ruby