Bump pillow from 5.1.0 to 6.2.0

Bumps [pillow](https://github.com/python-pillow/Pillow) from 5.1.0 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@5.1.0...6.2.0)

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

Author: dependabot[bot]

requirements.txt

@@ -15,7 +15,7 @@ mkl-random==1.0.1
 numba==0.40.1
 numpy==1.14.2
 olefile==0.46
-Pillow==5.1.0
+Pillow==6.2.0
 pycparser==2.18
 pyparsing==2.2.0
 python-dateutil==2.7.3