Log Message:
boost: updated to 1.66.0

1.66.0:
New Libraries
Beast:
Portable HTTP, WebSocket, and network operations using only C++11 and \ 
Boost.Asio, from Vinnie Falco.

CallableTraits:
A spiritual successor to Boost.FunctionTypes, Boost.CallableTraits is a \ 
header-only C++11 library for the compile-time inspection and manipulation of \ 
all 'callable' types. Additional support for C++17 features, from Barrett Adair.

Mp11:
A C++11 metaprogramming library, from Peter Dimov.