[DynInst_API:] [dyninst/dyninst] c6c4c0: Boost cleanup (#578)

[Tim Haines <noreply@xxxxxxxxxx>]

  Branch: refs/heads/master
  Home:   https://github.com/dyninst/dyninst
  Commit: c6c4c04f54da53992623ed2626fb5844b72a7b83
      https://github.com/dyninst/dyninst/commit/c6c4c04f54da53992623ed2626fb5844b72a7b83
  Author: Tim Haines <thaines.astro@xxxxxxxxx>
  Date:   2019-05-02 (Thu, 02 May 2019)

  Changed paths:
    M CMakeLists.txt
    A cmake/Boost.cmake
    A cmake/Modules/FindBoost.cmake
    M cmake/packages.cmake
    M cmake/shared.cmake

  Log Message:
  -----------
  Boost cleanup (#578)

Substantially changes how we handle Boost builds in Dyninst.

Fixes #563

- Tagged build layouts are now fully supported
- Boost is exported to the same install structure as Dyninst (fixes #563)
- All cmake variables that control Boost's build options are now available for the user to change via cache variables (e.g., -DBoost_USE_MULTITHREADED)
- Substantial error handling has been added
- Consolidates all Boost-related activities into cmake/Boost.cmake
- Makes Boost-1.61 the new minimum version (needed for Filesystem)
- Builds Boost-1.69 when building from source