Remove single owner field

The ownership is now stored in owners many to many relation, allowing to
have more than one owner.

Fixes #719
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/trans/migrations/0039_remove_project_owner.py

+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('trans', '0038_auto_20150810_1354'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='project',
+            name='owner',
+        ),
+    ]

weblate/trans/models/project.py

@@ -131,17 +131,6 @@ class Project(models.Model, PercentMixin, URLMixin, PathMixin):
             'Whether to allow updating this repository by remote hooks.'
         )
     )
-    owner = models.ForeignKey(
-        User,
-        verbose_name=ugettext_lazy('Owner'),
-        null=True,
-        db_index=True,
-        related_name='old_owned_projects',
-        blank=True,
-        help_text=ugettext_lazy(
-            'Owner of the project.'
-        )
-    )
     owners = models.ManyToManyField(
         User,
         verbose_name=ugettext_lazy('Owners'),