Add field to hold DCO for project

Issue #516
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/trans/migrations/0032_subproject_agreement.py

+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('trans', '0031_auto_20150415_1339'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='subproject',
+            name='agreement',
+            field=models.TextField(default=b'', help_text='Agreement which needs to be approved before user can translate this component.', verbose_name='Contributor agreement', blank=True),
+        ),
+    ]

weblate/trans/models/subproject.py

@@ -309,6 +309,15 @@ class SubProject(models.Model, PercentMixin, URLMixin, PathMixin):
         default='',
         help_text=ugettext_lazy('Optional URL with license details.'),
     )
+    agreement = models.TextField(
+        verbose_name=ugettext_lazy('Contributor agreement'),
+        blank=True,
+        default='',
+        help_text=ugettext_lazy(
+            'Agreement which needs to be approved before user can '
+            'translate this component.'
+        )
+    )
 
     # Adding new language
     new_lang = models.CharField(