No more C source files, no more necessity to use C-linkage. Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
Return an std::string to avoid memory management headaches. While doing that, convert time.c to C++ so that format_datetime directly returns an std::string. Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>