Squashed 'src/ripple/rocksdb/rocksdb/' content from commit 56589ab

git-subtree-dir: src/ripple/rocksdb/rocksdb
git-subtree-split: 56589ab81f6827ff7402e31b24a6d548f29a524f
Merge commit 'b156a49cff152fd52992a4823aaeafbaf70e564e' as 'src/ripple/rocksdb/rocksdb'
Make include paths relative
Add rocksdb module
Add RocksDB NodeStore backend
Comment out write to stdout
Set background thread name
Fix Workers thread name