release 1.2

- new framework: Restful and Websocket services use the same interface, so separate samples (Application and ApplicationWS) are combined back to one Application.
- DelayedTask and DelayedTaskList: simple abstraction on asio::deadline_timer
- http::Client new interface: uses Task abstraction as a deferred object
- url_encode() and base64_encode() are moved to the misc.hpp
- JSON logger configuration example (still under construction)
merge stable back to support `git describe`