ParaDict, an OCaml implementation of CTries for parallel dictionnaries

THIS IS A WORK IN PROGRESS

By original I mean the code described on wikipedia here, and in the papers in the notes 1 and 2 on that page.

On wiki there is this line bit = bmp & (1 << ((hashcode >> level) & 0x1F)) which is imho incorrect, as the and bmp is an error here and redundant with the and in the iinsert function.
In the paper they talk about a "32-bit hashcode space". I use OCaml's native int, which are either 31 or 63 bit long depending on the platform. This changes nothing in the logic, only slightly changes the maximum practical depth.