Add status query for total bytes used by a LevelDB instance
Add status query for total bytes used by a LevelDB instance

This commit adds a new LevelDB property "leveldb.total-bytes" that
returns the total bytes used by LevelDB for SSTs. This value is
equivalent to the sum of the reported per-level sizes shown in the
"leveldb.status" output.

tempbottle/leveldb-1,IMCG/levelDB,basho/leveldb,tempbottle/leveldb-1,IMCG/levelDB,IMCG/levelDB,icholy/leveldb,basho/leveldb,icholy/leveldb,basho/leveldb,tempbottle/leveldb-1,icholy/leveldb