Create TMPDIR for tests recursively

keystone/tests/tmp is missing in the sdist tarballs, so
we need to not only create keystone/tests/tmp/<pid> but also the
parent directory. Use os.makedirs for that.

Change-Id: I2f97bee517297b9fa239183c23ad1dfa52505bc9
Closes-Bug: #1296862

MANIFEST.in

@@ -20,4 +20,4 @@ graft keystone/tests
 graft tools
 graft examples
 recursive-include keystone *.json *.xml *.cfg *.pem README *.po *.pot *.sql
-global-exclude *.pyc *.sdx *.log *.db *.swp tests/tmp/*
+global-exclude *.pyc *.sdx *.log *.db *.swp keystone/tests/tmp/*

keystone/tests/core.py

@@ -89,7 +89,7 @@ TMPDIR = _calc_tmpdir()
 CONF = config.CONF
 
 exception._FATAL_EXCEPTION_FORMAT_ERRORS = True
-os.mkdir(TMPDIR)
+os.makedirs(TMPDIR)
 atexit.register(shutil.rmtree, TMPDIR)