If the user disables an account, this saves it so that on any
subsequent start-ups, the account won't be connected until the user
explicitly re-enables it.
ProtocolSettings were reworked to allow for publicly loading/saving
settings from BMessages, rather than solely from BViews.
In addition, all program-side disabling, enabling, and toggling of
accounts has been consolidated into ProtocolManager. This makes life
easier for other parts of the program that have to do these things
anyway.
Jaidyn Ann