expose custom logger configuration

[zaidoon1]

Per https://github.com/facebook/rocksdb/wiki/Logger#existing-logger-implementations , we can use a custom logger to get the logs to show up in the format we need and more importantly where we need. In my case, I want to use "StderrLogger | Pipes the messages to std::err equivalent" but this library doesn't appear to allow me to set this option.

[zaidoon1]

facebook pr to expose the c api has been merged: facebook/rocksdb#12262

will create the rust bindings once the c binding changes land in the rocksdb release