Removed a @TODO in sb_social_share_entity_get_properties() and added a descriptive comment.
t1103: Added logic to sb_social's hook_salesforce_queue_process_items_alter() implementation, to skip and un-queue an anonymous social share if the Contact_sharer__c field is marked (in the mapping) as non-nillable. When that field is required, anonymous shares can't be synced to Salesforce.