the version we have in-tree, but experience has shown that if systemwide
boost was installed at some point during build then junked by dpb build
was failing. Boo.
Note that in newer releases of kicad those bundled boost headers were removed,
and now cmake downloads boost tarball during build and patch its headers on
the fly. Yay.
https://lists.launchpad.net/kicad-developers/msg10503.html