Re-fix ImproperlyConfigured error when calling from CLI in Django 1.8 (#183)

[abbottc]

March 25th of last year, issue #183 was created and a fix was merged for it. Then on Nov 7th of last year, #215 was merged. Unfortunately, that merge removed the code which fixed #183. I ran into the problem described in #183 and through troubleshooting it, I saw the history I just described and verified that the issue was resolved by re-adding the code. This pull request re-adds the code along with a comment as to why it's there for some extra safety.

[kakulukia]

Since there are no updates to pyjade and its successor recently was deleted from pypi, I took the liberty to revive it: https://github.com/kakulukia/pypugjs

Version 5.0.1 has fixed the incompatibility with recent Django versions. In case you also updated you code base and want to continue using your jade/pug templates. :)