Revert "DEP: Update pytest dependency"

This reverts commit 23a8e0e.

Author: effigies

nipype/info.py

@@ -105,7 +105,7 @@ def get_nipype_gitversion():
 SCIPY_MIN_VERSION = '0.14'
 TRAITS_MIN_VERSION = '4.6'
 DATEUTIL_MIN_VERSION = '2.2'
-PYTEST_MIN_VERSION = '3.4'
+PYTEST_MIN_VERSION = '3.0'
 FUTURE_MIN_VERSION = '0.16.0'
 SIMPLEJSON_MIN_VERSION = '3.8.0'
 PROV_VERSION = '1.5.0'

requirements.txt

@@ -10,7 +10,7 @@ prov==1.5.0
 click>=6.6.0
 funcsigs
 configparser
-pytest>=3.4
+pytest>=3.0
 pytest-xdist
 pytest-env
 mock