rename file and add flow_ref parameter to it

pipelines/params/validity_thresholds.yaml

@@ -1,6 +1,10 @@
+
+flow_ref_tofware: &flow_ref 1.36
+flow_ref_correct: &flow_ref_correct 1.36
+
 # Get values from data/<station>/<year>/global_config.r
 # Define operational ranges for diagnostic variables
-operational_range:
+validity_thresholds:
   description : "Defines the value range of a particular variable"
   variables:
     VaporizerTemp_C :
@@ -13,6 +17,7 @@ operational_range:
       upper_lim : 500000 
 
     FlowRate_ccs :
+    # TODO: Define the range as a percentage around the alias variable &flow_ref_correct above defined.
       lower_lim : 1.23 
       upper_lim : 1.45