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

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

charts/generic/pod-network-loss/experiment.yaml

@@ -40,7 +40,7 @@ spec:
     - name: TARGET_CONTAINER
       value: ''
 
-     # provide lib image
+    # provide lib image
     - name: LIB_IMAGE
       value: 'gaiaadm/pumba:0.6.5' 
 
@@ -53,6 +53,10 @@ spec:
     - name: TOTAL_CHAOS_DURATION
       value: '60000' #in ms
 
+    # Period to wait before injection of chaos in sec
+    - name: RAMP_TIME
+      value: ''
+
     - name: LIB
       value: 'pumba'
     labels: