Use Python3 for tests

test-requirements.txt

@@ -2,9 +2,9 @@
 # tests with new APIs/semantics. We want to update versions deliberately.
 
 # flake8 must be listed before pylint to avoid dependency conflicts
-flake8==3.7.7
+flake8==3.7.9
 flake8-mutable==1.2.0
-flake8-print==3.1.0
-pylint==1.9.4
+flake8-print==3.1.4
+pylint==2.4.4
 setuptools-lint==0.6.0
-yamllint==1.15.0
+yamllint==1.20.0

tox.ini

@@ -1,8 +1,6 @@
 [tox]
-minversion=2.3.1
 envlist =
-    py{27,35}-{flake8,pylint}
-    py27-{yamllint,ansible_syntax}
+    py3-{flake8,pylint,yamllint,ansible_syntax}
 skipsdist=True
 skip_missing_interpreters=True
 
@@ -18,7 +16,6 @@ setenv =
 deps =
     -rrequirements.txt
     -rtest-requirements.txt
-    py35-flake8: flake8-bugbear==17.3.0
 
 commands =
     flake8: flake8 {posargs}