(refactor) add ramp_time env in generic experiments (#126)

Signed-off-by: ksatchit <ksatchit@mayadata.io>

charts/generic/container-kill/experiment.yaml

@@ -43,6 +43,10 @@ spec:
     - name: TARGET_CONTAINER
       value: ''
 
+    # Period to wait before injection of chaos in sec
+    - name: RAMP_TIME
+      value: ''
+
     # It only supports pumba
     - name: LIB
       value: 'pumba'
@@ -52,4 +56,4 @@ spec:
       value: 'gaiaadm/pumba:0.4.8' 
 
     labels:
-      name: container-kill
+      name: container-kill