Improve testing

.travis.yml

@@ -1,13 +1,49 @@
 sudo: false
+cache:
+  pip: true
 language: python
 python:
-  - "2.7"
-  - "3.4"
-  - "3.5"
-  - "3.6"
+- 2.7
+- 3.4
+- 3.5
+- &main_python_version 3.6
+before_install:
+- pip install -U pip setuptools
 install:
-  - if [[ $TRAVIS_PYTHON_VERSION == 3.5 || $TRAVIS_PYTHON_VERSION == 3.6 ]]; then pip install aiohttp==2.0.6 asynctest==0.10.0; fi
-  - pip install -q pep8==1.6.2
+- pip install -r test-requirements-py3.txt
 script:
-  - pep8 .
-  - python setup.py test
+- python setup.py test
+
+jobs:
+  fast_finish: true
+
+  include:
+  - stage: &lint_stage_name lint
+    python: *main_python_version
+    install:
+    - pip install pep8==1.6.2
+    script:
+    - pep8 .
+
+  - stage: &deploy_stage_name deploy to PYPI (triggered only for tagged commits)
+    python: *main_python_version
+    before_install: []
+    script: skip
+    deploy:
+      provider: pypi
+      distribution: sdist bdist_wheel
+      user: dblack
+      password:
+        secure: YOUR_ENCRYPTED_PASSWORD_HERE_https://docs.travis-ci.com/user/encryption-keys/
+      # Since commit https://github.com/travis-ci/dpl/commit/90b5e39
+      # it is default that Travis PYPI provider has `skip_upload_docs: true`
+      # set by default.
+      on:
+        tags: true
+        all_branches: true
+
+stages:
+- *lint_stage_name
+- test
+- name: *deploy_stage_name
+  if: tag IS present

setup.py

@@ -3,7 +3,7 @@
 
 
 setup(
-    setup_requires=['pbr==1.8.1'],
+    setup_requires=['pbr==3.1.1'],
     pbr=True,
     test_suite='nose.collector',
     platforms=['any'],

test-requirements-py3.txt

@@ -0,0 +1,2 @@
+aiohttp>=2.0,<2.3; python_version>="3.4"
+asynctest==0.10.0; python_version>="3.4"