Clarify the required versions of dependent packages.

Author: DWesl

requirements-dev.txt

@@ -1,3 +1,3 @@
 cython>=0.16
 numpy
-scipy
+scipy>-0.16.0

requirements.txt

@@ -1 +1 @@
-scipy
+scipy>=0.16.0

setup.cfg

@@ -29,12 +29,12 @@ license_files=
 tests_require=
     pytest-cov
     hypothesis[numpy]
-    scipy
+    scipy>=0.16.0
 install_requires=scipy
 setup_requires=
     cython>=0.16
     numpy
-    scipy
+    scipy>=0.16.0
 packages=find:
 python_requires= >=2.7, <4, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*
 

tox.ini

@@ -8,16 +8,16 @@ envlist = py27, py34, py35, py36, py37, py38, pypy, jython, distrib, docs
 requires =
     Cython>=0.16
     numpy
-    scipy
+    scipy>=0.16.0
 minversion = 1.7.2
 skip_missing_interpreters = true
 
 [testenv]
 deps =
     hypothesis[numpy]
-    scipy
+    scipy>=0.16.0
     pytest-cov
-    cython
+    cython>=0.16
 commands =
     pytest
 
@@ -26,9 +26,9 @@ deps=
     setuptools
     twine
     wheel
-    Cython
+    Cython>=0.16
     numpy
-    scipy
+    scipy>=0.16.0
 skip_install=true
 commands=
     {envpython} setup.py check
@@ -42,9 +42,9 @@ commands=
 changedir=doc
 deps=
     sphinx
-    Cython
+    Cython>=0.16
     numpy
-    scipy
+    scipy>=0.16.0
 commands=
     sphinx-build -q -W --keep-going -b html -d {envtmpdir}/doctrees source {envtmpdir}/html
     sphinx-build -q -W -b texinfo -d {envtmpdir}/doctrees source {envtmpdir}/texinfo