Bug 2103: Revert "Bug 2101: Do not block processing on transaction submit."

Turns out that the get was throttling the stats manager so
it didn't overwhelm the queue.

This reverts commit 6b3c2a9e446bf91942a48427e5592909a173a399.

Change-Id: I9f77a16a959594c65ed3e61b1265c56da620c1ba
Signed-off-by: Ed Warnicke <eaw@cisco.com>
Bug 2106: Refactored FlowCapableInventoryProvider to properly work with failures.

FlowCapableInventoryProvider was unable to continue if transaction chain
failed during construction of new transaction.

Refactored it in way, that it is able to reconstruct and retry transaction,
which failed because of previous transaction and retries it once
in new transaction chain. If it fails again, it continues with next batch.

Change-Id: I4a90a3b60b0a49d562c8648a779e790f55840b5d
Signed-off-by: Tony Tkacik <ttkacik@cisco.com>
BUG-2078  Stats not being collected from all nodes, dangling nodes left in oper data store after mininet disconnects
BUG-2049  DataStore failure in StatisticsManager

* fix performance issues
* fix occurrence zombie nodes
* fix NPE for StatCollector
* fix NPE for Meter/Group lists

Change-Id: I95a821aaf308bdb6e989c4a740aa014d5aaab4c2
Signed-off-by: Vaclav Demcak <vdemcak@cisco.com>
Merge changes I95a821aa,I4a90a3b6,I9f77a16a

* changes:
  BUG-2078  Stats not being collected from all nodes, dangling nodes left in oper data store after mininet disconnects BUG-2049  DataStore failure in StatisticsManager
  Bug 2106: Refactored FlowCapableInventoryProvider to properly work with failures.
  Bug 2103: Revert "Bug 2101: Do not block processing on transaction submit."