Directory restructure to add scenarios and experiments (#559)

* Updated dir struture with scenarios and experiments dir

Signed-off-by: Amit Kumar Das <amit.das@harness.io>

* Added icons

Signed-off-by: Amit Kumar Das <amit.das@harness.io>

experiments/cassandra/cassandra.chartserviceversion.yaml

@@ -0,0 +1,42 @@
+apiVersion: litmuchaos.io/v1alpha1
+kind: ChartServiceVersion
+metadata:
+  createdAt: 2020-04-14T10:28:08Z
+  name: cassandra
+  version: 0.1.3
+  annotations:
+    categories: Cassandra
+    chartDescription: Injects cassandra kubernetes chaos
+spec:
+  displayName: Cassandra Chaos
+  categoryDescription: >
+    Cassandra is a free and open-source, distributed, wide column store, NoSQL database management system designed to handle 
+    large amounts of data across many commodity servers, providing high availability with no single point of failure. 
+    It will install all the experiments which can be used to inject chaos into cassandra applications.
+  experiments:
+    - name: cassandra-pod-delete
+      description: ""
+  keywords:
+    - Kubernetes
+    - K8S
+    - Pod
+    - Cassandra
+  maintainers:
+    - name: ksatchit
+      email: karthik.s@mayadata.io
+  minKubeVersion: 1.12.0
+  provider:
+    name: Mayadata
+  links:
+    - name: Cassandra Website
+      url: http://cassandra.apache.org/
+    - name: Source Code
+      url: https://github.com/apache/cassandra
+    - name: Cassandra Slack
+      url: https://cassandra-slack.herokuapp.com
+    - name: Documentation
+      url: http://cassandra.apache.org/doc/latest/
+  icon:
+    - url: https://raw.githubusercontent.com/litmuschaos/chaos-charts/master/charts/cassandra/icons/cassandra.png
+      mediatype: image/png
+  chaosexpcrdlink: https://raw.githubusercontent.com/litmuschaos/chaos-charts/master/charts/cassandra/experiments.yaml