[FIX] When initializing the Trip properties, use the correct keys when accessing user defaults.

[treh]

Currently the childseat property is always initialized to false, because the wrong user defaults key is used.

Note: The user defaults key for child set is "childSeat" (camel case) while the storage key is "childseat" (lowercase). Both are persisted, so we can't unify them.

[ckrey]

Thanks for spotting those blunders