conversations: user search

src/AppDelegate.mm

src/ChooseContactVC.mm

src/ConversationVC.mm

src/CurrentCallVC.mm

src/LeaveMessageVC.mm

src/MessagesVC.mm

src/RingWindowController.mm

src/SmartViewVC.mm

src/utils.h

src/views/RingTableView.h

src/views/RingTableView.mm

ui/Base.lproj/RingWindow.xib