this is an internal copy of boost 1.71 (required modules)
It's used only when there is no system-wide boost available

How to build it:
- download latest boost tarball, unpack it
- ./bootstrap.sh
- ./b2 tools/bcp
- ./dist/bin/bcp process ../tmp
- copy content of tmp here

NOTE: boost 1.72+ requires a build change as boost.filesystem has a library that must be built for each platform