Update Django template reference URL from Django 1.7 to Django 1.11. Add migratons to update model definitions.

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

mayan/apps/metadata/migrations/0010_auto_20180823_2353.py

@@ -0,0 +1,25 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.11 on 2018-08-23 23:53
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('metadata', '0009_auto_20180402_0339'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='metadatatype',
+            name='default',
+            field=models.CharField(blank=True, help_text="Enter a template to render. Use Django's default templating language (https://docs.djangoproject.com/en/1.11/ref/templates/builtins/)", max_length=128, null=True, verbose_name='Default'),
+        ),
+        migrations.AlterField(
+            model_name='metadatatype',
+            name='lookup',
+            field=models.TextField(blank=True, help_text="Enter a template to render. Must result in a comma delimited string. Use Django's default templating language (https://docs.djangoproject.com/en/1.11/ref/templates/builtins/).", null=True, verbose_name='Lookup'),
+        ),
+    ]

mayan/apps/metadata/models.py

@@ -55,7 +55,7 @@ class MetadataType(models.Model):
         help_text=_(
             'Enter a template to render. '
             'Use Django\'s default templating language '
-            '(https://docs.djangoproject.com/en/1.7/ref/templates/builtins/)'
+            '(https://docs.djangoproject.com/en/1.11/ref/templates/builtins/)'
         ),
         verbose_name=_('Default')
     )
@@ -65,7 +65,7 @@ class MetadataType(models.Model):
             'Enter a template to render. '
             'Must result in a comma delimited string. '
             'Use Django\'s default templating language '
-            '(https://docs.djangoproject.com/en/1.7/ref/templates/builtins/).'
+            '(https://docs.djangoproject.com/en/1.11/ref/templates/builtins/).'
         ),
         verbose_name=_('Lookup')
     )