boost: Version Update -> 1.66.0

boost: Version Update -> 1.66.0

This package release updates boost to version 1.66.0.
Boost 1.66.0 brings three new header-only libs:
- Beast [1]: Portable HTTP, WebSocket, and network operations using only C++11
             and Boost.Asio, from Vinnie Falco.
- CallableTraits [2]: 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 [3]: A C++11 metaprogramming library, from Peter Dimov.

More info about this release, can be found in [4].

[1]: http://www.boost.org/doc/libs/1_66_0/libs/beast/doc/html/index.html
[2]: http://www.boost.org/doc/libs/1_66_0/libs/callable_traits/doc/html/index.html
[3]: http://www.boost.org/doc/libs/1_66_0/libs/mp11/doc/html/mp11.html
[4]: http://www.boost.org/users/history/version_1_66_0.html

Signed-off-by: Carlos Miguel Ferreira <carlosmf.pt@gmail.com>