Imported the AX_CXX_COMPILE_STDCXX_11 macro from the Autoconf Archive.

Source: http://www.gnu.org/software/autoconf-archive/ax_cxx_compile_stdcxx_11.html
Imported two AX_BOOST_* M4 macros from the Autoconf Archive.

Source: http://www.gnu.org/software/autoconf-archive/
Integrated with Travis CI for build status notifications.

See: http://about.travis-ci.org/docs/user/getting-started/
See: http://about.travis-ci.org/docs/user/build-configuration/
See: http://about.travis-ci.org/docs/user/languages/cpp/