- fix build with gcc-3.4;
- fix sortedp.c and zbogotest to handle empty files properly;
- add a 'test' target;
- use INFO and PLIST_FILES and nuke pkg-plist.
And yes, I know that adding HAVE_STRING_H to config.h.in is somewhat
hackish; the proper fix - a string.h check in configure.in - is on its
way to the bogosort developers :)
