Merge pull request #59 from bcwaldon/graceful-shutdown

Handle SIGINT/SIGTERM; remove machine proactively
bump(github.com/coreos/go-systemd): 4a3b33ed414ad42fddee2a4848c4cb9ad36a0677
feat(unit): Use dbus events to update JobState in Registry
Merge pull request #60 from bcwaldon/async-state

WIP: asynchronously update JobState in Registry
refactor(agent): Separate event handlers from Agent
refactor(agent): Separate event handlers from Agent
refactor(agent): Rename agent.EventListener to EventHandler
refactor(engine): Separate EventHandler from engine.Engine
refactor(engine): Drop nil-implemented event handlers
refactor(engine): Move capability code from event.go to engine.go
fix(agent): reschedule job when initial attempt fails
feat(agent): re-publish job offers on shutdown
fix(agent): be careful with the iterator when bidding
refactor(registry): log watch index
bump(code.google.com/p/go.crypto/ssh): initial checkout
feat(machine): Publish machine's eth0 IP to Registry
feat(corectl): Add journal cmd
refactor(corectl): Reimplement corectl status to use SSH
bump(github.com/coreos/go-etcd/etcd): 5c0151c64399ff9a8087c2e29ae96145ede7cfc2
feat(corectl): Tunnel commands over SSH