Rename 'storage' to 'buf' in Queue implementation.

And 'len' to 'buf_len'. Makes queue_len() clearer.
Add dynamic array.
Use _init() instead of _make() functions.

Bit more typing, but cleaner and less mallocy.
Add dynamic growth to hash table.

Also make it strdup() keys to be less surprising.
Fix broken vector test case.
Fix double increment of hash element count.

Caused premature growing.