Add context to unit tests

When running the unit tests we will now see which tests is being
run and the status of the test in question. This will help debugging,
triaging and cleaning things up.

Change-Id: I6d1458654d2fb6a8e814b17c4673bb9337fac4ec

tools/ostestr_compat_shim.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+# preserve old behavior of using an arg as a regex when '--' is not present
+case $@ in
+  (*--*) ostestr $@;;
+  ('') ostestr;;
+  (*) ostestr --regex "$@"
+esac

tox.ini

@@ -14,8 +14,7 @@ deps = -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
        -r{toxinidir}/doc-requirements.txt
 commands =
-  find . -type f -name "*.pyc" -delete
-  python setup.py testr --slowest --testr-args='{posargs}'
+  {toxinidir}/tools/ostestr_compat_shim.sh {posargs}
 
 [testenv:cover]
 whitelist_externals = sh