Update README.md

Author: guessi

README.md

@@ -8,6 +8,10 @@
 
 Blazing fast single purpose cli for CloudTrail log filtering, written in golang
 
+## 🔢 Prerequisites
+
+* An IAM Role/User with [cloudtrail:LookupEvents](https://docs.aws.amazon.com/awscloudtrail/latest/APIReference/API_LookupEvents.html) permission.
+
 ## 🚀 Quick start
 
 ```bash