Update django-environ to 0.4.5

[pyup-bot]

This PR updates django-environ from 0.4.0 to 0.4.5.

Changelog

0.4.5

--------------------------
Added
+++++
- Support for Django 2.0
- Support for smart casting
- Support PostgreSQL unix domain socket paths
- Tip: Multiple env files

Changed
+++++++
- Fix parsing option values None, True and False
- Order of importance of engine configuration in db_url_config

Removed
+++++++
- Remove django and six dependencies

0.4.4

--------------------------

Added
+++++
- Support for django-redis multiple locations (master/slave, shards)
- Support for Elasticsearch2
- Support for Mysql-connector
- Support for pyodbc
- Add __contains__ feature to Environ class

Changed
+++++++
- Fix Path subtracting

0.4.3

--------------------------
Changed
+++++++
- Rollback the default Environ to os.environ

0.4.2

-------------------------
Added
+++++
- Confirm support for Django 1.11.
- Support for Redshift database URL

Changed
+++++++
- Fix uwsgi settings reload problem (55)
- Update support for django-redis urls (109)

0.4.1

----------------------------
Added
+++++
- Add support for Django 1.10

Changed
+++++++
- Fix for unsafe characters into URLs
- Clarifying warning on missing or unreadable file. Thanks to nickcatal
- Fix support for Oracle urls
- Fix support for django-redis

Links

• PyPI: https://pypi.org/project/django-environ
• Changelog: https://pyup.io/changelogs/django-environ/
• Repo: https://github.com/joke2k/django-environ/issues