[boost] boost/context/all.hpp missing in 1.68.0beta1

Subject: [boost] boost/context/all.hpp missing in 1.68.0beta1
From: Roger Leigh (rleigh_at_[hidden])
Date: 2018-07-11 16:30:57

Is this intentional, or an unintentional regression?

I was using this header in the CMake component checks to verify the 
presence of Boost.Context, and this is now breaking.  I can update it to 
use a different header which has been present since 1.61, but this seems 
like a compatibility break, hence the question.

Thanks,
Roger