RestClient renamed poolsize key

RestClient does not have POOL_SIZE_KEY anymore.
From the source it is probably renamed to HTTP_POOL_SIZE.
The previous constant value was poolsize and the new constant
is http.poolsize.

Upgrading the R2, Data, Pegasus libraries along with this change.
Fix for QuotaLimitingStore: Passing storestats for the current store instead of the aggregate
Merge pull request #194 from arunthirupathi/PoolSizeRename

RestClient renamed poolsize key
Merge pull request #196 from icefury71/quota_per_store_stats_fix

Fix for QuotaLimitingStore: Passing storestats for the current store ins...