How can I change calendar/contacts sync setting for iPhone?
If you go to Settings > Mail, Contacts, Calendars > iCloud (should be the first account)  and scroll down to Contacts.  

When you scroll to "Contacts" you must slide it off. I did this by sliding the "Contact" button from right to left and swiped away the green.  I was prompted to "What would you like to do with the previously synced iCloud contacts on your iPhone.  I chose "Keep on My Phone". 

Then you can use iTunes like you used to do and select the Contacts you want to be synced. I prefer this way.