Updated pysparklines dependency does not support Python 2, need to set version in requirements.txt

[RedKrieg]

I see your requirements specifies pysparklines but no version and I just wanted to let you know that the recently released 1.0 does not support Python versions before 3, so could cause your project issues. I would change your requirements.txt to use pysparklines==0.9 to resolve this problem until your project is fully Python 3 compatible.