Update book

book/src/interop-cheat-sheet.md

@@ -9,6 +9,7 @@ interop testing.
 	- [Avoid port clashes when starting multiple nodes](#port-bump)
 	- [Specify a custom slot time](#slot-time)
 - Using the beacon node HTTP API:
+	- [Pretty-print the genesis state and state root](#http-state)
 	- [Curl a node's ENR](#http-enr)
 	- [Curl a node's connected peers](#http-peer-ids)
 	- [Curl a node's local peer id](#http-peer-id)
@@ -82,6 +83,15 @@ $ ./beacon_node testnet -t 500 recent 8
 Examples assume there is a Lighthouse node exposing a HTTP API on
 `localhost:5052`. Responses are JSON.
 
+<a name="http-state"></a>
+### Pretty-print the genesis state and state root
+
+Returns the genesis state and state root in your terminal, in YAML.
+
+```
+$ curl --header "Content-Type: application/yaml" "localhost:5052/beacon/state?slot=0"
+```
+
 <a name="http-enr"></a>
 ### Get the node's ENR
 

book/src/interop-scenarios.md

@@ -25,8 +25,11 @@ cheat-sheet](./interop-cheat-sheet.md).
 To start a brand-new beacon node (with no history) use:
 
 ```
-$ ./beacon_node testnet -f quick 8 1567222226
+$ ./beacon_node testnet -f quick 8 <GENESIS_TIME>
 ```
+
+Where `GENESIS_TIME` is in [unix time](https://duckduckgo.com/?q=unix+time&t=ffab&ia=answer).
+
 > Notes:
 >
 > - This method conforms the ["Quick-start

book/src/interop-tips.md

@@ -1 +0,0 @@
-# Interop Tips & Tricks