test1: test utvector init/fini
test2: test utvector of int, push, next
test3: test utvector push, pop, extend
test4: test utvector_copy
test5: test utvector of utstring
test6: test utvector of utstring more ops
test7: test utvector of utstring even more ops
test8: test utextend past initial size int
test9: test utextend past initial size utstring
test10: test utvector_pop on empty list (int)
test11: test utvector_pop on empty list (utstring)
test12: test utvector head/tail (int)
test13: test utvector head/tail (utstring)
test14: test utvector_shift (int)
test15: test utvector_shift (utstring)
test16: test utvector_elt
