Remove the -Wdeprecated-declarations from violite.h and convert sprintfs to snprintfs

server-main/include/violite.h has the following fragment for MacOSX:

/* apple deprecated openssl in MacOSX Lion */

#ifdef __APPLE__

#pragma GCC diagnostic ignored "-Wdeprecated-declarations"

#endif

The MacOSX versions that actually do have openssl headers are long being deprecated. Nowadays MacOSX binaries are compiled against the stock openssl library and headers and these do not have deprecation warnings built into them.

It's time to remove this warning suppression.

But the removal results in 100 or so "sprintf is deprecated" warnings.

So these should be fixed as well.