Suggestions for osg-notify

[DrDaveD]

I have these suggestions to osg-notify. I sent them to @bbockelm by slack but I don't know if he noticed.

1. I don't think that --recipients should be required if --oim-recipients is given
2. I think --oim-recipients should have an option to do both resources and vos, not just either
3. I think it would be helpful for the command to give a little feedback to the user upon success, such as the number of recipients that were sent the message.