sorcery: Add additional observer capabilities.

Add new global, instance and wizard observers.
instance_created
wizard_registered
wizard_unregistered
instance_destroying
instance_loading
instance_loaded
wizard_mapped
object_type_registered
object_type_loading
object_type_loaded
wizard_loading
wizard_loaded

Tested-by: George Joseph

Review: https://reviewboard.asterisk.org/r/4215/


git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/12@428999 f38db490-d61c-443f-a65b-d21fe96a405b