create ConnectionState before adding to HostMap (#535)

We have a few small race conditions with creating the HostInfo.ConnectionState
since we add the host info to the pendingHostMap before we set this
field. We can make everything a lot easier if we just add an "init"
function so that we can set this field in the hostinfo before we add it
to the hostmap.

CHANGELOG.md

@@ -53,10 +53,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   will immediately switch to a preferred remote address after the reception of
   a handshake packet (instead of waiting until 1,000 packets have been sent).
   (#532)
-  
+
 - A race condition when `punchy.respond` is enabled and ensures the correct
   vpn ip is sent a punch back response in highly queried node. (#566)
 
+- Fix a rare crash during handshake due to a race condition. (#535)
+
 ## [1.4.0] - 2021-05-11
 
 ### Added