Boost assumes variadic templates are always available in GCC 4.4+, but
they aren't since we don't build with -std=c++11.
This applies the patch that fixed the issue in boost 1.57:
eec8085549
See also: https://svn.boost.org/trac/boost/ticket/10500
Github-Pull: #6280
Rebased-From: b19a88b2a0e7bd9ef603055bc8e1ef058673025d