#5 missing argument to RegisterWarning causes SIGSEGV

[Denis Rystsov]

main() does not supply a matching argument for %s format, which causes coredump in Lubutnu 12.10 with GCC 4.7.0.
Here's the proposed patch:
src/main.cc
1289c1289
< "CRMOD", "cannot resolve module %s", "<module>", 0);
---
> "CRMOD", "cannot resolve module %s" );