Bump pillow from 5.3.0 to 6.2.0 (#48)

Bumps [pillow](https://github.com/python-pillow/Pillow) from 5.3.0 to 6.2.0.
- [Release notes](https://github.com/python-pillow/Pillow/releases)
- [Changelog](https://github.com/python-pillow/Pillow/blob/master/CHANGES.rst)
- [Commits](python-pillow/Pillow@5.3.0...6.2.0)

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

requirements.txt

@@ -2,7 +2,7 @@ Django==2.1.4
 django-autoslug-iplweb==1.9.4
 django-widget-tweaks==1.4.3
 mysqlclient==1.3.14
-Pillow==5.3.0
+Pillow==6.2.0
 pycodestyle==2.4.0
 pytz==2018.7