Release v0.1.0 (#571)

Mostly optimizations, but also includes some breaking changes.
Importantly:

1. Rebroadcast backoff is now configurable. This should be backwards
compatible with other nodes as long as the defaults are specified in the
manifest (other nodes will ignore those defaults). But it's definitely
an API breaking change.
2. If configured, we now attempt to align instances when catching up.
3. We've bumped the protocol version to 3 so we can detect nodes that
have these features.

Additionally:

1. We've added a ton of metrics, and improved many of the existing ones.
2. We've optimized message validation significantly.

version.json

@@ -1,3 +1,3 @@
 {
-  "version": "v0.0.7"
+  "version": "v0.1.0"
 }