add total duration in 'hamster list' command (#380)

* add total duration in 'hamster list' command

* use stuff.format_duration for totals

Author: madtibo

src/hamster-cli

@@ -332,11 +332,14 @@ class HamsterClient(object):
         print("-" * min(row_width, 80))
 
         cats = []
+        total_duration = dt.timedelta()
         for cat, duration in sorted(by_cat.items(), key=lambda x: x[1], reverse=True):
-            cats.append("%s: %s" % (cat, "%.1fh" % (stuff.duration_minutes(duration) / 60.0)))
+            cats.append("{}: {}".format(cat, stuff.format_duration(duration)))
+            total_duration += duration
 
         for line in word_wrap(", ".join(cats), 80):
             print(line)
+        print("Total: ", stuff.format_duration(total_duration))
 
         print()