- fixed up find request back-off logic
https://github.com/openpeer/op-stack-cpp/issues/28

- don't send peer identity request until incoming peer-location-find notify has been received
https://github.com/openpeer/op-stack-cpp/issues/30

- only shutdown peer connection when no possibility to connect was found
https://github.com/openpeer/op-stack-cpp/issues/29