trivial: refresh template with recent best practices

- add releasenotes to tox
- inherit requirements when is it possible in tox
- switch to hacking 2.x
- add gitignore rules related to reno

Change-Id: Id448fc31474fd29fb0799e96c5f1bb07c83f00bd

oslo.{{cookiecutter.module_name}}/lower-constraints.txt

@@ -3,6 +3,6 @@
 # process, which may cause wedges in the gate later.
 
 Babel==1.3.0
-hacking==0.10.0
+hacking==2.0.0
 mypy==0.720
 oslotest==1.5.1

oslo.{{cookiecutter.module_name}}/test-requirements.txt

@@ -2,7 +2,7 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-hacking<0.11,>=0.10.0
+hacking>=2.0.0,<2.1.0 # Apache-2.0
 mypy>=0.720 # MIT
 oslotest>=1.5.1
 stestr>=2.0.0 # Apache-2.0

oslo.{{cookiecutter.module_name}}/tox.ini

@@ -37,12 +37,19 @@ commands =
 [testenv:docs]
 whitelist_externals =
     rm
-commands =
-    rm -rf doc/build doc/source/reference/api
-    sphinx-build -W -b html doc/source doc/build/html
 deps =
     -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
     -r{toxinidir}/doc/requirements.txt
+commands =
+    rm -rf doc/build doc/source/reference/api
+    sphinx-build -W --keep-going -b html doc/source doc/build/html {posargs}
+
+[testenv:releasenotes]
+whitelist_externals = rm
+deps = {[testenv:docs]deps}
+commands =
+  rm -rf releasenotes/build
+  sphinx-build -a -E -W -d releasenotes/build/doctrees --keep-going -b html releasenotes/source releasenotes/build/html
 
 [testenv:mypy]
 commands =

tools/test_tox_targets.sh

@@ -30,4 +30,4 @@ def test_api():
     pass
 EOF
 
-tox -e pep8,py36,docs,lower-constraints,cover
+tox -e pep8,py36,docs,lower-constraints,cover,releasenotes