Log message:
Import kyotocabinet-1.2.51 as wip/kyotocabinet.

Kyoto Cabinet is a library of routines for managing a database.
The database is a simple data file containing records, each is
a pair of a key and a value. Every key and value is serial bytes
with variable length. Both binary data and character string can
be used as a key and a value. Each key must be unique within a
database. There is neither concept of data tables nor data types.
Records are organized in hash table or B+ tree.