Running the test file fails

[SeanHeelan]

After removing the -std=c89 requirement mentioned in issue #8 I compiled the code and ran the produced test binary. The following happens:

$ ./test
test: test.c:172: test_iterating: Assertion `strncmp((char *)hashset_iterator_value(iter), "Karen", 5) == 0' failed.
Aborted (core dumped)