support meta arrays

pandora_upload/__init__.py

@@ -59,7 +59,14 @@ def main():
                 print('\ninvalid metadata argument, format is -m "key=value"')
                 sys.exit(1)
             k, v = m.split('=', 1)
-            meta[k] = v
+            if k in meta:
+                if isinstance(meta[k], str):
+                    meta[k] = [meta[k]]
+                meta[k].append(v)
+            elif v[0] == '[' and v[-1] == ']':
+                meta[k] = v[1:-1]
+            else:
+                meta[k] = v
     files = opts.files
     if not files:
         parser.print_help()