Reformats MultiPaxosContext so that log strings are not broken
Fixes some HA tests and supporting code

ClusterManager.masterSeesMembers now waits for exactly the argument, instead of >=
TestPullUpdates.makeSureUpdatePullerGetsGoingAfterMasterSwitch is un-Ignored
TestPullUpdates.shouldPullUpdatesOnStartupNoMatterWhat has a latch added waiting
 on the condition of the slave leaving, removing a race.
HaBeanIT.leftInstanceDisappearsFromMemberList has a condition added so the
 master actually observes the leave from the slave instead of erroneously
 assuming that shutdown() blocks until the instance leaves formally
Changed tests with clusters of 2 to 3 so they lose instances correctly
Merge pull request #1616 from digitalstain/ha-test-fixen

HA test fixes