Python tests are now run trough stestr.

Number of the environment variables passed to tox envs was
reduced from all, to just one.

This is preparatory step for further test developmet.
Reviews for test infrastructure, refactoring and coverage
will be on branches from this one.

tools/validate_files.py:
	Changed encoding to utf-8 to prevent
	linting error.

Signed-off-by: Jiri Podivin <jpodivin@redhat.com>
Change-Id: Idd82aecb7b66433396639ed800a33b109a06e11a

.stestr.conf

@@ -0,0 +1,3 @@
+[DEFAULT]
+test_path=${TEST_PATH:-./tripleo_validations/tests}
+top_dir=./

test-requirements.txt

@@ -14,3 +14,4 @@ testtools>=2.2.0 # MIT
 reno>=3.1.0 # Apache-2.0
 netaddr>=0.7.18 # BSD
 pre-commit # MIT
+stestr>=3.0.1 # Apache-2.0

tools/validate-files.py

@@ -22,7 +22,7 @@ def exit_usage():
 
 
 def validate_library_file(file_path):
-    with open(file_path) as f:
+    with open(file_path, encoding='utf-8') as f:
         file_content = f.read()
         if 'DOCUMENTATION = ' not in file_content \
                 or 'EXAMPLES = ' not in file_content:

tox.ini

@@ -7,7 +7,7 @@ ignore_basepython_conflict = True
 [testenv]
 basepython = python3
 usedevelop = True
-passenv = *
+passenv = TERM
 setenv =
   ANSIBLE_CALLBACK_PLUGINS={toxinidir}/callback_plugins
   ANSIBLE_LOOKUP_PLUGINS={toxinidir}/lookup_plugins
@@ -21,8 +21,13 @@ setenv =
   # paramiko CryptographyDeprecationWarning: https://github.com/ansible/ansible/issues/52598
   PYTHONWARNINGS=ignore:DEPRECATION::pip._internal.cli.base_command,ignore::UserWarning
   PIP_DISABLE_PIP_VERSION_CHECK=1
-commands = python setup.py test --slowest --testr-args='{posargs}'
-sitepackages = True
+  PIP_+  VIRTUAL_ENV={envdir}
+  LANG=en_US.UTF-8
+  LANGUAGE=en_US:en
+  LC_ALL=C
+  HOME={envdir}
+commands =
+    stestr run --slowest --color {posargs}
 deps =
     -c {env:TOX_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
     -r {toxinidir}/requirements.txt