make flock() locking non-blocking to match fcntl() implementation
make flock() locking non-blocking to match fcntl() implementation

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