Phone number ambiguity fix

To get the phone numbers of contacts, there are different approaches:

 - If the Ripple is used for debugging PhoneGap applications, then
	 contact.phoneNumbers[0] is a phone number of the contact.
 - On Android devices,
   contact.phoneNumbers[0].value is a phone number of the contact. You
	 should use value to get the phone number.
 - Not much testing has been done on iOS devices, needs to be tested.