Old tox couldn't rely on requirements reference

Author: penguinolog

.travis.yml

@@ -12,6 +12,8 @@ install:
 script: tox
 after_success:
   - coveralls
+before_deploy:
+  - pip install -r CI_REQUIREMENTS.txt
 deploy:
   - provider: pypi
     distributions: sdist bdist_wheel

CI_REQUIREMENTS.txt

@@ -0,0 +1 @@
+funcsigs>=1.0

tox.ini

@@ -18,20 +18,16 @@ deps =
     pytest
     pytest-cov
     pytest-sugar
+    py27: funcsigs>=1.0
+    pypy: funcsigs>=1.0
     py27: mock
     pypy: mock
-    {[base_deps]deps}
+    py34: typing
 
 commands =
     py.test -vv --junitxml=unit_result.xml --cov-config .coveragerc --cov-report html --cov=logwrap {posargs:test}
     coverage report --fail-under 90
 
-[base_deps]
-deps =
-    py27: funcsigs>=1.0
-    pypy: funcsigs>=1.0
-    py34: typing
-
 [testenv:venv]
 commands = {posargs:}
 
@@ -56,15 +52,17 @@ commands = pep257 logwrap
 
 [testenv:install]
 deps =
-    {[base_deps]deps}
+    py34: typing
+    -r{toxinidir}/CI_REQUIREMENTS.txt
 usedevelop = False
 commands = pip install ./ -vvv -U
 
 [testenv:pylint]
 basepython = python3.5
 deps =
+    py34: typing
     pylint
-    funcsigs>=1.0
+    -r{toxinidir}/CI_REQUIREMENTS.txt
 commands = pylint logwrap
 
 [flake8]
@@ -87,15 +85,16 @@ count = True
 
 [testenv:docs]
 deps =
+    py34: typing
     sphinx
-    {[base_deps]deps}
+    -r{toxinidir}/CI_REQUIREMENTS.txt
 commands = python setup.py build_sphinx
 
 [testenv:upload_docs]
 deps =
     sphinx
     sphinx-pypi-upload
-    {[base_deps]deps}
+    -r{toxinidir}/CI_REQUIREMENTS.txt
 commands = python setup.py build_sphinx upload_sphinx
 
 [testenv:bandit]