Use tests repo for common role test requirements

Using tox for requirements management requires in-repo
requirements files for all our repositories. Rather than
do that, we make use of the tests repo to capture our
common requirements and use this to install them.

This reduces our review requirement rate and simplifies
maintenance for us for the tox config. It also makes it
usable with 'Depends-On', which is marvellous!

The tox requirements definitions for docs/releasenotes
builds are left in-place as those are standard entries
across the community. If that changes at some point, we
can re-assess those entries too.

Depends-On: https://review.openstack.org/579208
Change-Id: Id66614618f4d2c552435015f9911f63e7fc89c5a

test-requirements.txt

@@ -1,9 +0,0 @@
-# The order of packages is significant, because pip processes them in the order
-# of appearance. Changing the order has an impact on the overall integration
-# process, which may cause wedges in the gate later.
-bashate>=0.2 # Apache-2.0
-flake8<2.6.0,>=2.5.4 # MIT
-pyasn1>=0.1.8 # BSD
-pyOpenSSL>=0.14 # Apache-2.0
-requests>=2.14.2 # Apache-2.0
-ndg-httpsclient>=0.4.2;python_version<'3.0' # BSD

tox.ini

@@ -8,8 +8,6 @@ envlist = docs,linters,functional
 usedevelop = True
 install_command =
     pip install -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt} {opts} {packages}
-deps =
-    -r{toxinidir}/test-requirements.txt
 commands =
     /usr/bin/find . -type f -name "*.pyc" -delete
 passenv =
@@ -76,38 +74,24 @@ commands =
     bash -c "{toxinidir}/tests/common/test-bashate.sh"
 
 
-[testenv:ansible]
-deps =
-    {[testenv]deps}
-    -rhttps://git.openstack.org/cgit/openstack/openstack-ansible-tests/plain/test-ansible-deps.txt
-
-
 [testenv:ansible-syntax]
-deps =
-    {[testenv:ansible]deps}
 commands =
     bash -c "{toxinidir}/tests/common/test-ansible-syntax.sh"
 
 
 [testenv:ansible-lint]
-deps =
-    {[testenv:ansible]deps}
 commands =
     bash -c "{toxinidir}/tests/common/test-ansible-lint.sh"
 
 
 [testenv:functional]
-deps =
-    {[testenv:ansible]deps}
 commands =
     bash -c "{toxinidir}/tests/common/test-ansible-functional.sh"
 
 
 [testenv:linters]
-deps =
-    -r{toxinidir}/doc/requirements.txt
-    {[testenv:ansible]deps}
 commands =
+    bash -c "{toxinidir}/tests/common/test-ansible-env-prep.sh"
     {[testenv:pep8]commands}
     {[testenv:bashate]commands}
     {[testenv:ansible-lint]commands}