Updated changelog and version

Updated major version to 0.18.0

v0.17.5

Version 0.16.0

Fixed served unable to start on mac os

Changed http_endpoint to be an inner class of webserver.

This avoids the class being publicly accessible in a cleaner way because it avoids using friends as a mechanism to allow instantiation within stl structures

Upgraded version

Update travis configuration file to match code requirements

version 0.11.1