calc v2.14.3.5 release

The following are the changes in this release:

Under macOS, to reduce dependency chains, we remove functions
and data that are unreachable by the entry point or exported
symbols.  In particular, the macOS linker is used with both
"-dead_strip" and "-dead_strip_dylibs".

The libcalc shared library is now linked with libcustcalc.