[boost] Reducing dependencies

Subject: [boost] Reducing dependencies
From: Antony Polukhin (antoshkka_at_[hidden])
Date: 2018-03-25 09:18:48

Hello,

I've noted that many libraries depend on container_hash while it
depends only on a single header from Boost.Detail library
https://pdimov.github.io/boostdep-report/master/module-levels.html

Can we move "boost/detail/container_fwd.hpp" into Boost.Core or into
Boost.ContainerHash? This will break the circular dependency, move the
Boost.ContainerHash on level 4 and improve levels of Intrusive,
Container, CircularBuffer, Unordered, Algorithm, Test, TypeIndex, Any,
Function, Functional, ScopeExit, Signals, MultiArray, Variant.

-- 
Best regards,
Antony Polukhin