fix the checks and typos

Author: vinit Kumar

dj_elastictranscoder/models.py

@@ -1,6 +1,7 @@
 from django.db import models
 from django.contrib.contenttypes.models import ContentType
-if django.version > 1.8:
+import django
+if django.get_version() > '1.8':
     from django.contrib.contenttypes.fields import GenericForeignKey
 else:
     from django.contrib.contenttypes.generic import GenericForeignKey