This commit removes the previous `MaxShard` tracking and replaces
it with an `Available Shards` set tracking. This allows sparse shard
tracking without implicitly tracking all shards in between.
refactor handler Close func to use errgroup to be a bit less messy.
refactor pilosa.Server closing to actually return an underlying error if one occurs
add option to pilosa/test.Cluster and pilosa/server.Command to control close
timeout. currently is only used by the http handler, but conceivably could be
passed as a parameter to other subsystems of pilosa/server.Command
The http internal client's FragmentBlocks and Blockdata methods were being used
incorrectly, and incorrect respectively. One was not being passed a node URI by
monitorAntiEntropy, and the other was always using the defaultURI regardless of
what was passed to it. Antientropy was doubling not working because of this. I
think this crept in pretty recently, so hasn't actually affected anyone.
I exposed a SyncData method on Server so that we can invoke the anti entropy
task manually instead of trying to set up the interval so that it will run and
then sleeping and waiting for it to run. Now that this test works the way it
does, the other anti entropy test is obsolete, and I deleted it.
gossip now takes a single "MemberServer" which is implemented by server. Several
interfaces have been removed.
MemberServer contains ReceiveMessage which is a superset of the functionality of
ReceiveEvent, LocalStatus and HandleRemoteStatus are all that's left of
StatusHandler - ClusterStatus was not used and is gone. The Node() method is
actually a subset of LocalStatus() functionality. Maybe we should break up
localstatus or remove Node... not sure.
Remove BroadcastReceiver test which was a bit silly.
NodeEvent can now be unexported, and is.
