[Wasm] Load factor and Initial Capacity are computed / handled outside the HT classes
Currently, the users of the Wasm hash table are responsible for computing initial capacity and using the load factor (LF). That is not only bad design that breaks encapsulation, but this can also have severe performance impacts.
A big problem with the current design is that the LF is treated equally between open adressing (OA) and chained hashing, despite them having very different meanings. While a load factor of 2 is absolutely sane for chained hashing, that's totally impossible for OA. Vice versa, an LF of 0.7 might be a good trade off between space requirements and lookup performance for an OA HT, but a chained HT might suffer from 30% unused buckets, wasting space AND degrading performance.