Add a "message_context" option for PJSIP endpoints.



git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/12@411157 f38db490-d61c-443f-a65b-d21fe96a405b
Prevent duplicate sorcery wizards from being applied to sorcery object types.

This commit contains several changes to sorcery:

1) Application of sorcery configuration based on module name is automatically performed
when sorcery is opened for a module.
2) Sorcery will not attempt to apply the same wizard to an object type more than once.
3) Sorcery gives more exact results when attempting to apply a wizard, whether as the
default or based on configuration.

Sorcery unit tests still pass for me after making these changes.

Review: https://reviewboard.asterisk.org/r/3326



git-svn-id: http://svn.asterisk.org/svn/asterisk/branches/12@411159 f38db490-d61c-443f-a65b-d21fe96a405b