Add likes, update templates

gallery/models/photo.py

@@ -43,6 +43,13 @@ class Photo(models.Model):
         self.views += 1
         self.save()
 
+    def get_next(self):
+        return self.__class__.objects.filter(taken_at__gt=self.taken_at, album=self.album.id).order_by('taken_at').first()
+
+    def get_prev(self):
+        return self.__class__.objects.filter(taken_at__lt=self.taken_at, album=self.album.id).order_by('-taken_at').first()
+
+
     def save(self, *args, **kwargs):
         self.exif_data = Exif(self.photo.path)
         datetime_taken = getattr(self.exif_data, 'datetimeoriginal', datetime.now)()