In create(), only apply the result insertId when it is non-zero. Fixes problem where apps that  manage their own 'id' column (i.e. non-autoincrement) in a Sails model would (falsely) receive <instance>.id of zero in the create callback.
Merge pull request #39 from kenhunt/create-insertId

In create(), only apply the result insertId when it is non-zero. Fixes p...