hashtable: Improve performance

Hashtable now stores data in an array and indices for data in buckets.

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
EA: Pass converted x for evaluation

Signed-off-by: Amitay Isaacs <amitay@gmail.com>
EA: Pass batch_mode to Logger initialization correctly

Signed-off-by: Amitay Isaacs <amitay@gmail.com>