Fix factory boy dependency (#373)

* Fix factory boy dependency

* fix factory-boy version in setup.py and requirements-development.txt

* Fix setup.py factory boy dependency

* Add an explanation about factory_boy version pinning

Include a link to the GitHub issue so a future dev will know when the dependency can be unpinned.

Author: santiavenda2

requirements-development.txt

@@ -5,11 +5,13 @@ isort
 mock
 pytest>=2.9.0,<3.0
 pytest-django
+# factory_boy is currently broken at 2.9 and above. See: https://github.com/pytest-dev/pytest-factoryboy/issues/47
+factory-boy<2.9.0
 pytest-factoryboy
 recommonmark
 Sphinx
 sphinx_rtd_theme
 tox
 mock
 django-debug-toolbar
-packaging==16.8
+packaging==16.8

setup.py

@@ -105,6 +105,7 @@ def get_package_data(package):
     setup_requires=pytest_runner + sphinx + wheel,
     tests_require=[
         'pytest-factoryboy',
+        'factory-boy<2.9.0',
         'pytest-django',
         'pytest>=2.8,<3',
         'django-polymorphic',