Remove unnecessary django_version compat

this is not really used and elsewhere we do:
from django import VERSION as django_version

Author: atodorov

pylint_django/compat.py

@@ -22,10 +22,3 @@
     except ImportError:
         from astroid.util import Uninferable
 
-try:
-    django = __import__("django")
-    django_version = django.VERSION
-except ImportError:
-    # if not available, will be handled by the django_installed checker
-    django_version = (1, 5)
-