Fix tensorflow to tensorflow-eigen

Created by: wilsonmr

Should hopefully close #485 (closed) and close #615 (closed)

Means that we don't use the version of tensorflow built against MKL

I want to emphasise that I don't really know what that means other than it's not using some intel optimizations but it seems to solve the growing memory issue on linux and the runtime error on mac which both appear to be caused by some weird linking to different versions of libraries