Fixes inability to create nodes when privacy is anyone with link.  #3132

os_activity was failing to validate the privacy.  It was expecting a boolean.  2 is not a boolean and confused the hell out of the entity wrapper.

Instead of a bool, I'm checking if the privacy equals public.  Otherwise, it's private.
Removing confusing int cast #3132
Re-add (int) cast.  It's expecting 0 or 1, not really a bool.  #3132
Merge pull request #3135 from openscholar/3132-bool_privacy

Fixes inability to create nodes when privacy is anyone with link.  #3132