fixed nk summary error

rowers/nkimportutils.py

@@ -192,6 +192,24 @@ def get_nk_summary(workoutdata,strokedata):
     maxhr = strokedata['heartRate'].max()
     pwr = workoutdata['avgPower']
 
+    if dist is None: # pragma: no cover
+        dist = 0
+
+    if spm is None: # pragma: no cover
+        spm = 0
+
+    if avghr is None: # pragma: no cover
+        avghr = 0
+
+    if avgdps is None: # pragma: no cover
+        avgdps = 0
+
+    if maxhr is None: # pragma: no cover
+        maxhr = 0
+
+    if pwr is None: # pragma: no cover
+        pwr = 0
+
     sep = "|"