- added caching at services level
resolves https://github.com/openpeer/op-services-cpp/issues/3

- fix bug where HTTP status code was interpretted wrongly

- added routine to copy from output JSON write buffer to secure buffer, related to:
https://github.com/openpeer/op-stack-cpp/issues/13

- added caching mechanism to auto-reply when contents haven't changed, related to:
resolves https://github.com/openpeer/op-stack-cpp/issues/9

- removed bootstrapper SRV lookup
resolves https://github.com/openpeer/op-stack-cpp/issues/14