RocksDB changes to support unity build:
* Remove extra definition of TotalFileSize
* Remove extra definition of ClipToRange
* Move EncodedFileMetaData out from anonymous namespace
* Move version_set Saver to its own namespace
* Move some symbols into a named namespace
* Move symbols out of anonymous namespace (prevents warning)
* Make BloomHash inline
Merge branch 'missing-commit' of github.com:vinniefalco/rippled into develop