Bug 3020: Use leader version in LeaderStateChanged

Modified the ShardManager to store the leader's version obtained from the
LeaderStateChanged message in the ShardInformation and propagate to the
RemotePrimaryShardFound message in response to FindPrimary.

ActorContext#findPrimaryShardAsync sets the leader's version in the
PrimaryShardInfo based on the FindPrimary response. If the response is
LocalPrimaryShardFound, it sets it to CURRENT_VERSION, otherwise it sets
it from the RemotePrimaryShardFound response.

RemoteTransactionContextSupport#setPrimaryShard checks the leader's
version to determine if it can utilize the direct tx modification
preparation on the shard actor.

Change-Id: I1defe03dea27dfb652cdc1e0a02fa70c6e454035
Signed-off-by: Tom Pantelis <tpanteli@brocade.com>