Summary:
Complete some refactoring called for in https://github.com/facebook/rocksdb/issues/6148. Somehow I got some 'make format' in here for files I didn't change, but that should be OK. (I'm not sure why "hide whitespace changes" doesn't seem to help in review.)
Not addressed in this PR: some operations simply print to stdout rather than failing on discovering a bad status or inconsistency.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6195
Differential Revision: D19131067
Pulled By: pdillinger
fbshipit-source-id: 4f416e6b792023989ef119f385fe122426cb825d
873331fe49