Merge branch 'hotfix/v0.12.2' into development

Conflicts:
	apps/common/__init__.py
	apps/documents/forms.py
	apps/feedback/__init__.py
	apps/history/__init__.py
	apps/main/__init__.py
	apps/scheduler/api.py
	apps/sources/models.py
	docs/releases/index.rst
	requirements/production.txt
	settings.py
	urls.py

apps/documents/models.py

@@ -38,6 +38,7 @@ from .managers import DocumentPageTransformationManager
 from .utils import document_save_to_temp_dir
 from .literals import (RELEASE_LEVEL_FINAL, RELEASE_LEVEL_CHOICES,
     VERSION_UPDATE_MAJOR, VERSION_UPDATE_MINOR, VERSION_UPDATE_MICRO)
+from .exceptions import NewDocumentVersionNotAllowed
 
 # document image cache name hash function
 HASH_FUNCTION = lambda x: hashlib.sha256(x).hexdigest()
@@ -171,8 +172,11 @@ class Document(models.Model):
     def size(self):
         return self.latest_version.size
 
-    def new_version(self, file, comment=None, version_update=None, release_level=None, serial=None):
+    def new_version(self, file, user=None, comment=None, version_update=None, release_level=None, serial=None):
         logger.debug('creating new document version')
+        if not self.is_new_versions_allowed(user=user):
+            raise NewDocumentVersionNotAllowed
+
         if version_update:
             new_version_dict = self.latest_version.get_new_version_dict(version_update)
             logger.debug('new_version_dict: %s' % new_version_dict)
@@ -538,8 +542,14 @@ class DocumentVersion(models.Model):
             return None
 
     def rename(self, new_name):
+        new_filename, new_extension = os.path.splitext(new_name)
         name, extension = os.path.splitext(self.filename)
-        self.filename = u''.join([new_name, extension])
+        
+        # Preserve existing extension if new name doesn't has one
+        if new_extension:
+            extension = new_extension
+
+        self.filename = u''.join([new_filename, extension])
         self.save()
 
     @property