SalesforceManager-fetchContacts.swift

    func fetchContacts(completion completion: (contacts: [SalesforceContact], error: NSError?) -> ()) {
        //TODO: Confirm that user is authenticated
        let request = SFRestAPI.sharedInstance().requestForQuery("SELECT Id, FirstName, LastName, Email FROM Contact")
        
        SFRestAPI.sharedInstance().sendRESTRequest(request, failBlock: { (error) in
            //Handle the error
            print("sendRESTRequest error: \(error.localizedDescription)")
        }) { (response) in
                //Parse the response
            print("sendRESTRequest response")
            guard let records = response["records"] as? [[String : AnyObject]] else {
                let error = NSError(domain: self.errorDomain, code: -100, userInfo: nil)
                completion(contacts: [], error: error)
                return
            }
            let contacts = records.map{ SalesforceContact(dictionary: $0) }
            completion(contacts: contacts, error: nil)
        }
    }