Setup for fluxCD app-distributed-cloud repo

This commit is to create the tox and zuul setup for the
app-distributed-cloud repo.

Test Plan:
PASS - Zuul Verified +1

Story: 2011312
Task: 51846

Change-Id: I7a03a6da0bb2951f411fb5a61932cec1095b19d8
Signed-off-by: Hugo Brito <hugo.brito@windriver.com>

.zuul.yaml

@@ -0,0 +1,8 @@
+---
+- project:
+    check:
+      jobs:
+        - openstack-tox-linters
+    gate:
+      jobs:
+        - openstack-tox-linters

requirements.txt

@@ -0,0 +1 @@
+# Nothing

test-requirements.txt

@@ -0,0 +1,3 @@
+# hacking pulls in flake8
+hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
+bashate >= 0.2 # Apache-2.0

tox.ini

@@ -0,0 +1,56 @@
+[tox]
+envlist = linters
+minversion = 4.0
+skipsdist = True
+sitepackages=False
+
+[testenv]
+basepython = python3
+usedevelop = True
+
+install_command = pip install -v -v -v \
+    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/starlingx/root/raw/branch/master/build-tools/requirements/debian/upper-constraints.txt} \
+    {opts} {packages}
+setenv =
+   VIRTUAL_ENV={envdir}
+   OS_STDOUT_CAPTURE=1
+   OS_STDERR_CAPTURE=1
+   OS_DEBUG=1
+   OS_LOG_CAPTURE=1
+deps =
+  -r{toxinidir}/requirements.txt
+  -r{toxinidir}/test-requirements.txt
+allowlist_externals =
+  bash
+
+passenv =
+    XDG_CACHE_HOME
+
+
+[testenv:bashate]
+# Treat all E* codes as Errors rather than warnings using: -e 'E*'
+commands =
+  bash -c "find {toxinidir}                    \
+         -not \( -type d -name .?\* -prune \) \
+         -type f                              \
+         -not -name \*~                       \
+         -not -name \*.md                     \
+         -name \*.sh                          \
+         -print0 | xargs -r -n 1 -0 bashate -v   \
+         -e 'E*'"
+
+[testenv:linters]
+commands =
+    {[testenv:bashate]commands}
+
+[testenv:pep8]
+description = Dummy environment to allow flake8 to be run in subdir tox
+
+[testenv:pylint]
+description = Dummy environment to allow pylint to be run in subdir tox
+
+[testenv:black]
+description = Dummy environment to allow black to be run in subdir tox
+
+[testenv:bandit]
+description = Dummy environment to allow bandit to be run in subdir tox