Add improvements to the metadata URL encoding and decoding to support ampersand characters as part of the metadata value. GitLab issue #529. Thanks to Mark Maglana @relaxdiego for the report.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

mayan/apps/sources/models.py

@@ -14,7 +14,7 @@ from django.core.files import File
 from django.core.files.base import ContentFile
 from django.db import models, transaction
 from django.utils.encoding import (
-    force_bytes, force_str, force_text, python_2_unicode_compatible
+    force_bytes, force_text, python_2_unicode_compatible
 )
 from django.utils.timezone import now
 from django.utils.translation import ugettext_lazy as _