Sync the list of headers visible with SHARED=symlinks with those visible with SHARED=copies.
Sync the list of headers visible with SHARED=symlinks with those
visible with SHARED=copies.

Inspired by:	njl

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase