Move codecov to tox.ini

.travis.yml

@@ -6,15 +6,14 @@ matrix:
       dist: xenial
       sudo: true
       env: TOXENV=py37-test
-      after_success:
-        - codecov
     - python: 3.7
       dist: xenial
       sudo: true
       env: TOXENV=lint
 
 install:
-  - pip install --upgrade pip codecov tox
+  - pip install --upgrade pip
+  - pip install tox
 
 script:
   - tox

tox.ini

@@ -7,9 +7,11 @@ envlist =
 
 [testenv]
 deps =
+passenv = CI TRAVIS TRAVIS_*
 extras = test
 commands =
     pytest --cov=./libp2p tests/
+    codecov
 basepython =
     py37: python3.7