Resolve some issue with tox.ini, setup.cfg

- Use constraints for documentation targets
- Indicate support for Python 3.7

Change-Id: I5f068d199e70cb7c2f0f71972bb0f81e025795fe
Signed-off-by: Stephen Finucane <sfinucan@sfinucan.users.ipa.redhat.com>

setup.cfg

@@ -17,6 +17,7 @@ classifier =
     Programming Language :: Python :: 2.7
     Programming Language :: Python :: 3
     Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
 
 [files]
 packages =
@@ -40,5 +41,5 @@ keywords = _ gettext ngettext l_ lazy_gettext
 mapping_file = babel.cfg
 output_file = oslo_versionedobjects/locale/oslo_versionedobjects.pot
 
-[wheel]
+[bdist_wheel]
 universal = true

tox.ini

@@ -1,45 +1,45 @@
 [tox]
-minversion = 2.0
-envlist = py36,py27,pep8
+minversion = 3.1
+envlist = py27,py36,py37,pep8
+basepython = python3
+ignore_basepython_conflict = true
 
 [testenv]
-setenv =
-    VIRTUAL_ENV={envdir}
-    BRANCH_NAME=master
-install_command = pip install {opts} {packages}
 deps =
-  -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+  -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
   -r{toxinidir}/test-requirements.txt
 commands = stestr run --slowest {posargs}
 
-[testenv:py27]
-basepython = python2.7
-
 [testenv:pep8]
-basepython = python3
-deps =
-  -r{toxinidir}/test-requirements.txt
 commands =
   flake8
   # Run security linter
   bandit -r oslo_versionedobjects tests -n5 --skip B303
 
 [testenv:venv]
-basepython = python3
 commands = {posargs}
 
+[testenv:cover]
+commands = python setup.py test --coverage --coverage-package-name=oslo_versionedobjects --testr-args='{posargs}'
+
 [testenv:docs]
-basepython = python3
-deps = -r{toxinidir}/doc/requirements.txt
+deps =
+  -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
+  -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -W -b html doc/source doc/build/html
 
-[testenv:cover]
-basepython = python3
-commands = python setup.py test --coverage --coverage-package-name=oslo_versionedobjects --testr-args='{posargs}'
+[testenv:releasenotes]
+deps = {[testenv:docs]deps}
+commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
+
+[testenv:lower-constraints]
+deps =
+  -c{toxinidir}/lower-constraints.txt
+  -r{toxinidir}/test-requirements.txt
+  -r{toxinidir}/requirements.txt
 
 [flake8]
 # E123, E125 skipped as they are invalid PEP-8.
-
 show-source = True
 ignore = E123,E125
 builtins = _
@@ -47,15 +47,3 @@ exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build
 
 [hacking]
 import_exceptions = oslo_versionedobjects._i18n
-
-[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:lower-constraints]
-basepython = python3
-deps =
-  -c{toxinidir}/lower-constraints.txt
-  -r{toxinidir}/test-requirements.txt
-  -r{toxinidir}/requirements.txt