docs: link for basic operato articles (#643)

Author: csviri

Diff for: docs/documentation/intro-operators.md

@@ -7,6 +7,12 @@ permalink: /docs/intro-operators
 
 # Introduction To Operators
 
-On this page we selected a collection of resources to introduce you to the concepts of Kubernetes Operators.
+This page provides a selection of articles that gives an introduction to Kubernetes operators.
 
+## Operators in General
 
+ - [Introduction of the concept of Kubernetes Operators](https://blog.container-solutions.com/kubernetes-operators-explained)
+ - [Operator pattern explained in Kubernetes documentation](https://kubernetes.io/docs/concepts/extend-kubernetes/operator/) 
+ - [An explanation why Java Operators makes sense](https://blog.container-solutions.com/cloud-native-java-infrastructure-automation-with-kubernetes-operators) 
+ - [What are the problems an operator framework is solving](https://csviri.medium.com/deep-dive-building-a-kubernetes-operator-sdk-for-java-developers-5008218822cb)
+