Added missing #include <utility> and qualified
make_pair with std:: to library_status.cpp.
Added missing headers to make1.c and missing prototypes
to builtin.h
Modified execunix.c to add support for terminating
processes that consume too much cpu or that hang and
fail to consume cpu at all. This in support of the
bjam -lx option.
http://svn.boost.org/trac/boost/ticket/1266#comment:2