TODO:
* try to make parts/apicheck.pl automatically find NEED_ #defines
* implement snprintf with newSVpvf for >= 5.004, which is safer?
* add support for my_vsnprintf?
* try to perform some core consistency checks:
- check if 'd' flag in embed.fnc matches with
supplied documentation
- check if all public API is documented
* check (during make regen?) if MAX_PERL in PPPort_pm.PL
needs to be updated
* see if we can implement sv_catpvf() for < 5.004
* MULTICALL ?
* improve apicheck (things like utf8_mg_pos_init() are
not currently checked)
* more documentation, more tests
* Resolve dependencies in Makefile.PL and remind of
running 'make regen'