Don't play with "../.." in includes for h_macros.h; deal with it centrally.
Minor fixes.

h_macros need strlcat and random ugh, please someone remove this header.
define _NETBSD_SOURCE so those are defined.

Convert the libposix, libprop, librt, libskey and libutil tests to ATF.
Initial work from the GSoC 2008 project by Lukasz Strzygowski.