Stop testing python2.7

Train was the last release supporting python2. Let's rip the bandaid
off.

Change-Id: I48705450552bb2ecc12a080b1c8b3e1b7efd2800

setup.cfg

@@ -13,8 +13,6 @@ classifier =
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
     Programming Language :: Python
-    Programming Language :: Python :: 2
-    Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.6
     Programming Language :: Python :: 3.7

tox.ini

@@ -1,10 +1,11 @@
 [tox]
 minversion = 2.0
-envlist = linters,docs,py27,py37,molecule
+envlist = linters,docs,py37,molecule
 skipdist = True
 
 [testenv]
 usedevelop = True
+basepython = python3
 install_command = pip install {opts} {packages}
 passenv = *
 setenv =
@@ -39,7 +40,6 @@ deps = bindep
 commands = bindep test
 
 [testenv:debug]
-basepython = python3
 commands = oslo_debug_helper {posargs}
 
 [testenv:pep8]
@@ -95,13 +95,11 @@ commands =
 #    {[testenv:yamllint]commands}
 
 [testenv:releasenotes]
-basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 commands =
     sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:cover]
-basepython = python3
 deps =
     -r {toxinidir}/requirements.txt
     -r {toxinidir}/test-requirements.txt
@@ -109,7 +107,6 @@ deps =
 commands = python setup.py test --coverage --testr-args='{posargs}'
 
 [testenv:docs]
-basepython = python3
 deps =
   -r {toxinidir}/doc/requirements.txt
   -r {toxinidir}/molecule-requirements.txt
@@ -123,7 +120,6 @@ extensions = .rst
 ignore = D001
 
 [testenv:lower-constraints]
-basepython = python3
 deps =
   -c{toxinidir}/lower-constraints.txt
   -r{toxinidir}/test-requirements.txt

zuul.d/layout.yaml

@@ -1,7 +1,6 @@
 - project:
     templates:
     - tripleo-multinode-container-minimal
-    - openstack-python-jobs
     - openstack-python3-ussuri-jobs
     - tripleo-validations-molecule-jobs
     - check-requirements