StaticHashTable:
- erase(iterator&) now actually alters the iterator and iterator++() handles
it properly
- clear() also sets count to zero
- operator=(const StaticHashTable&) doesn't crash after a previous transfer
- operator(), operator==() and operator!=() added
HashTable:
- operator=(const HashTable&) gets tableSize if required, eg, after a
previous transfer)
HashSet / Map
- add xfer<...> constructor for underlying HashTable
