* agent: Watches now reset their index back to zero after an error, or if the index goes backwards, which allows watches to recover after a server restart with fresh state. [GH-2621]
* agent: HTTP health checks now upport custom method and headers. [GH-1184, GH-2474, GH-2657, GH-3106]
* agent: Increased the graceful leave timeout from 5 to 15 seconds. [GH-3121]
* agent: Added additional logging when the agent handles signals and when it exits. [GH-3124]
* build: Added support for linux/arm64 binaries. [GH-3042]
* build: Consul now builds with Go 1.8.3. [GH-3074]
* ui: Added a sticky scroll to the KV side panel so the KV edit box always stays in place. [GH-2812]