util functions and test

	connect_timeout
	set_nonblock
	construct_sockaddr
hash functions and test

	create_hashtable
	insert_hashtable
	remove_hashtable
	rehash_hashtable
	get_hashtable
	clear_hashtable
	destroy_hashtable

	hash_string

	insert_hashelem
	remove_hashelem

	test_ring
	hash_get_prime
	get_buck