fix compile error

The %ld thing didn't work in scanf,
in that case just stop using size_t
and use long instead.
remove time(NULL) from random seed

1) the proper header wasn't being included,
so this was a compile error on some boxes
2) I really don't like consciously adding
non-determinism to the code.
SCOREC/core is not a crypto library, please
make your seeds deterministic between runs.