avoid dev dependencies on ci tests (aio-libs#2438)

.travis.yml

@@ -36,12 +36,12 @@ _helpers:
   <<: *_reset_steps
   install:
   - *upgrade_python_toolset
-  - pip install -U -r requirements/dev.txt
+  - pip install -U -r requirements/ci.txt
 - &_doc_base
   <<: *_lint_base
   install:
   - *upgrade_python_toolset
-  - pip install -U -r requirements/dev.txt -r requirements/doc.txt -r requirements/doc-spelling.txt
+  - pip install -U -r requirements/ci.txt -r requirements/doc.txt -r requirements/doc-spelling.txt
   after_failure: cat docs/_build/spelling/output.txt
   addons:
     apt:

requirements/ci-wheel.txt

@@ -1,21 +1,22 @@
-pip==9.0.1
-flake8==3.5.0
-pyflakes==1.6.0
-coverage==4.4.1
+async-timeout==2.0.0
+brotlipy==0.7.0
 cchardet==2.1.1
-cython==0.27.1
 chardet==3.0.4
+coverage==4.4.1
+cython==0.27.1
+flake8==3.5.0
+gunicorn==19.7.1
 isort==4.2.15
-tox==2.9.1
 multidict==3.3.0
-async-timeout==2.0.0
-pytest==3.2.3
+pip==9.0.1
+pyflakes==1.6.0
 pytest-cov==2.5.1
 pytest-mock==1.6.3
-gunicorn==19.7.1
+pytest==3.2.3
+towncrier==17.8.0
+tox==2.9.1
 twine==1.9.1
 yarl==0.13.0
-brotlipy==0.7.0
 
 # Using PEP 508 env markers to control dependency on runtimes:
 aiodns==1.1.1; platform_system!="Windows"  # required c-ares will not build on windows

requirements/dev.txt

@@ -2,4 +2,3 @@
 ipdb==0.10.3
 pytest-sugar==0.9.0
 ipython==6.2.1
-towncrier==17.8.0