Updated Preferred Chain (markdown)

Preferred-Chain.md

@@ -4,16 +4,18 @@ If the ACME CA provides multiple cert chain, you can use `--preferred-chain` to
 
 1. For letsencrypt.org Staging Server:
 
+https://letsencrypt.org/docs/staging-environment/
+
     There are 2 chains provided:
 
     |   Name            |  Default  |
     |-------------------|-----------|
-    |   Fake LE Root X1 | Yes       |
-    |   Fake LE Root X2 |   No     |
+    |   "(STAGING) Pretend Pear X1" | Yes       |
+    |   "(STAGING) Bogus Broccoli X2" |   No     |
 
     You select the ca like:
 ```
-acme.sh  --issue -d example.com .....  --test    --preferred-chain  "Fake LE Root X2"
+acme.sh  --issue -d example.com .....  --test    --preferred-chain  "(STAGING) Bogus Broccoli X2"
 ```
 
 You can also use part of the name: