Fix setup

setup.py

@@ -9,6 +9,9 @@ from setuptools import setup, find_packages, dist
 dist.Distribution(dict(setup_requires=['bob.extension', 'bob.blitz'] + bob_packages))
 from bob.blitz.extension import Extension, Library, build_ext
 
+from bob.extension.utils import load_requirements
+build_requires = load_requirements()
+
 packages = ['boost']
 boost_modules = ['system', 'python']