Migrate openstack modules as a collection

Migrate accordin to Ansible guidelines [1[]] and tool
migrate.py [2]
Also fixed ALL ansible-test sanity issues

Add pep8 and linter job with runs ansible-test sanity test.

[1] https://etherpad.openstack.org/p/openstack-ansible-modules
[2] https://github.com/ansible-community/collection_migration

Change-Id: Ib2b1c8f23aacfca95304132bfe5c4cdedbea0520

tox.ini

@@ -0,0 +1,49 @@
+[tox]
+minversion = 3.1
+envlist = pep8
+skipsdist = True
+ignore_basepython_conflict = True
+
+[testenv]
+skip_install = True
+install_command = pip3 install {opts} {packages}
+passenv = OS_*
+setenv =
+    VIRTUAL_ENV={envdir}
+    LANG=en_US.UTF-8
+    LANGUAGE=en_US:en
+    LC_ALL=C
+    OS_LOG_CAPTURE={env:OS_LOG_CAPTURE:true}
+    OS_STDOUT_CAPTURE={env:OS_STDOUT_CAPTURE:true}
+    OS_STDERR_CAPTURE={env:OS_STDERR_CAPTURE:true}
+deps =
+    -r{toxinidir}/test-requirements.txt
+commands = stestr run {posargs}
+           stestr slowest
+
+[testenv:pep8]
+commands =
+    flake8
+
+[testenv:linters]
+passenv = *
+commands =
+    ansible-galaxy collection build --force {toxinidir} --output-path {toxinidir}/build_artifact
+    ansible-galaxy collection install {toxinidir}/build_artifact/openstack-cloud-1.0.0.tar.gz --force -p {toxinidir}
+    /bin/bash -c "cd ansible_collections/openstack/cloud && ansible-test sanity"
+
+[testenv:venv]
+deps =
+    -r{toxinidir}/test-requirements.txt
+commands = {posargs}
+
+[flake8]
+# W503 Is supposed to be off by default but in the latest pycodestyle isn't.
+#      Also, both openstacksdk and Donald Knuth disagree with the rule. Line
+#      breaks should occur before the binary operator for readability.
+# H4 are rules for docstrings. Maybe we should clean them?
+# E501,E402,H301,H236,F401,E128 are ignored so we can import the existing
+#      modules unchanged and then clean them in subsequent patches.
+ignore = W503,H4,E501,E402,H301,H236,F401,E128,W504,F841,F403,F405
+show-source = True
+exclude=.venv,.git,.tox,dist,doc,*lib/python*,*egg,build