Batch Locking

[krishnalpatel]

Provide ability to acquire lock on multiple keys in a single dynamo db query (BatchPutItem or BatchWriteItem)
Currently, the implementation of acquireLock is such that it can only acquire lock for a single key at a time, using PutItem
We have a use case where we need to iterate over a list of objects and acquire a lock on each before proceeding further. When this list hits a considerable size, having multiple dynamodb queries increases the latency manifolds. We were looking on acquiring all the locks in a single query and release them in a single query as well to avoid multiple dynamodb queries and thereby improving latency.