Nhse d34 openriak.i10 logger

[martinsumner]

Adds additional config for logs, plus also a config item logger.config_function.

The logger.config_function can be mapped to a logger config function using the case statement:

https://github.com/OpenRiak/riak/blob/66cdea92c376824e5a773c1453ee8f534ed2e86d/priv/riak.schema#L115-L125

There are two logger config functions that have been added to riak_logger - one to produce logs as they were in openriak-3.2, and another to produce as proposed for openriak-3.4.

[martinsumner]

It might be preferable to simply make the type of the logger.config_function an atom, and remove the case statement in the translation - and just call riak_loggerPconfig:Fun(Conf, fun cuttlefish:conf_get/2) where Fun is the atom.

This would make it easy to add further functions for processing configuration, without having to update the main Riak repo.

[tburghart]

Perhaps rather than specifying a function name, we specify a module name (conforming to a behavior). This would alter some of my comments on OpenRiak/riak_logger#1 ...
Also a cleaner approach for org-specific config modules that aren't published.