Start instance only after staging upload succeeds

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Extract snapshot from bootstrap

Signed-off-by: Maria Shaldibina <mariash@pivotallabs.com>
Extract instance manager from bootstrap

Signed-off-by: Mark Rushakoff <mrushakoff@pivotallabs.com>
Extract filter instances by message from bootstrap to instance registry

Signed-off-by Mark Rushakoff <mrushakoff@pivotallabs.com>
dea.heartbeat always contains all dea instances

this allows consumers of the dea.heartbeat to trust that the heartbeat
represents the entire state of the dea.  this, in turn, allows consumers
to perform set-diff style saves. (hm9000 uses this to reduce its write
load)
Auto-merge remote-tracking branch 'upstream/master'