Add support for Python 3.8

Author: di

setup.cfg

@@ -15,6 +15,7 @@ classifier =
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7
+    Programming Language :: Python :: 3.8
 
 [files]
 packages =

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py{36,37},lint
+envlist = py{36,37,38},lint
 skipsdist = True
 
 [testenv]
@@ -15,7 +15,7 @@ whitelist_externals = find
                       go
                       docker
 [testenv:lint]
-basepython = python3.7
+basepython = python3.8
 commands =
     flake8
 
@@ -28,6 +28,9 @@ commands = pytest -v -s --tb=long --cov=cloudevents {toxinidir}/cloudevents/test
 [testenv:py37]
 commands = pytest -v -s --tb=long --cov=cloudevents {toxinidir}/cloudevents/tests
 
+[testenv:py38]
+commands = pytest -v -s --tb=long --cov=cloudevents {toxinidir}/cloudevents/tests
+
 [flake8]
 ignore = H405,H404,H403,H401,H306,S101,N802,N803,N806,I202,I201
 show-source = True