(cherry picked from commit c6e4014136aa3d81ecd4288150b3eefca9849b0b)

See https://github.com/facebook/rocksdb/wiki/Prefix-Seek-API-Changes

For better logging I'm going to inject the rocksdb info_logger into the C++ Wrapper classes
=> The classes on the options object have a member to a DB specific logger
=> This c++ classes can only belong to a SINGLE db
=> For simplicity make this requirement also for the options object itself

which makes py3 support possible

Use sys.getfilesystemencoding() for encoding