tensorflow-gpu dependency

[bytosaur]

Hey Michal,
I was wandering if it's necessary to use 'tensorflow-gpu'... I am on a Mac and would like to export the multi-person-pose-model from your other repo as SavedModel. Since there is no such package for my distro and 'tensorflow-gpu' fused with 'tensorflow', I thought it is more convenient to just use 'tensorflow'. Same applies for the other repo :)
have a good day :)