Fix travis build in Py3.4 by pinning a version dependency.
Fix travis build in Py3.4 by pinning a version dependency.

scoder/cython,da-woods/cython,cython/cython,da-woods/cython,scoder/cython,da-woods/cython,cython/cython,scoder/cython,scoder/cython,cython/cython,cython/cython,da-woods/cython