Only use stestr and tempest run in tempest tox jobs

Now that we're starting to unify everything on a single test runner we
should only be using either tempest run or stestr (which tempest run
will use internally in the near future). This commit changes the
coverage job to use stestr and removes the ostestr job as part of that
effort.

Change-Id: I5972346b8dbef4a57c733f85ceeeeca425bf263e

tox.ini

@@ -36,7 +36,17 @@ commands =
 commands = oslo-config-generator --config-file tempest/cmd/config-generator.tempest.conf
 
 [testenv:cover]
-commands = python setup.py testr --coverage --testr-arg='tempest\.tests {posargs}'
+setenv =
+  {[testenv]setenv}
+  PYTHON=coverage run --source tempest --parallel-mode
+commands =
+  coverage erase
+  find . -type f -name "*.pyc" -delete
+  stestr --test-path ./tempest/tests run {posargs}
+  coverage combine
+  coverage html -d cover
+  coverage xml -o cover/coverage.xml
+  coverage report
 
 [testenv:all]
 envdir = .tox/tempest
@@ -50,17 +60,6 @@ commands =
     find . -type f -name "*.pyc" -delete
     tempest run --regex {posargs}
 
-[testenv:ostestr]
-sitepackages = {[tempestenv]sitepackages}
-# 'all' includes slow tests
-setenv =
-    {[tempestenv]setenv}
-    OS_TEST_TIMEOUT={env:OS_TEST_TIMEOUT:1200}
-deps = {[tempestenv]deps}
-commands =
-    find . -type f -name "*.pyc" -delete
-    ostestr {posargs}
-
 [testenv:all-plugin]
 sitepackages = True
 # 'all' includes slow tests