code: public Contact addContact(String contact) {
  		Contact prop = new Contact(contact);
  		setContact(prop);
  		return prop;
  	}
docs: Sets the contact for the free/busy entry.
  @param contact the contact (e.g. "ACME Co - (123) 555-1234")
  @return the property that was created
  @see <a href="http://tools.ietf.org/html/rfc5545#page-109">RFC 5545
  p.109-11</a>
  @see <a href="http://tools.ietf.org/html/rfc2445#page-104">RFC 2445
  p.104-6</a>