More descriptive documentation

README.md

@@ -14,6 +14,11 @@ pip install github3.py
 
 * Place the script under */usr/local/sbin/mail2github_issues.py*.
 
+* Adjust the following variables accordingly:
+    * TOKEN = 'XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX'
+    * USER = 'exampledev'
+    * REPO = 'myrepo'
+
 * Edit */etc/aliases*:
 
 ```