Added HTTP Chaos Toxicity (#563)

* improved description of http experiments

Signed-off-by: avaakash <as86414@gmail.com>

* Added toxicity env in http chaos

Signed-off-by: avaakash <as86414@gmail.com>

Signed-off-by: avaakash <as86414@gmail.com>

experiments/generic/pod-http-modify-body/experiment.yaml

@@ -87,6 +87,12 @@ spec:
     - name: PROXY_PORT
       value: "20000"
     
+    # toxicity is the probability of the request to be affected
+    # provide the percentage value in the range of 0-100
+    # 0 means no request will be affected and 100 means all request will be affected
+    - name: TOXICITY
+      value: "100"
+
     # network interface on which the proxy will listen
     - name: NETWORK_INTERFACE
       value: "eth0"