tidied up data stack initialization

Signed-off-by: Jake Bromberg <jake.bromberg@gmail.com>
converting enum to NS_ENUM

Signed-off-by: Jake Bromberg <jake.bromberg@gmail.com>
reorganizing code slightly

Signed-off-by: Jake Bromberg <jake.bromberg@gmail.com>
eliminated commonInit from LockscreenMediaController and converted it to KVO blocks

Signed-off-by: Jake Bromberg <jake.bromberg@gmail.com>