Add the "%token_class" directive to the LEMON parser generator. This opens up

Add the "%token_class" directive to the LEMON parser generator.  This opens up
the possibility of simplifying the parser.  Also remove all calls to
sprintf(), strcpy(), and strcat() from LEMON to avoid compiler warnings
on OpenBSD.  (Aside:  It is this change to avoid harmless compiler warnings
that was the cause of the reason spat of bugs.)

FossilOrigin-Name: 8eb48c04bd0a14031488b3160fde67307eb8b35d