Expose a few symbols as public interface rather than private.
Expose a few symbols as public interface rather than private.

Note: the *64 interfaces are no longer exposed via zlib.h but were keep
as public interfaces;

Note 2: this commit would break applications that uses the moved symbols
directly.

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