python3-testtools: add it for oeqa

- It is required by oeqa, add it so that we can add nativesdk-python3-testtools
  to buildtools-tarball.
- The original one is python-testtools_2.3.0.bb which is from meta-openstack
  layer, I divided it into python-testtools.inc and python3-testtools_2.2.0.bb,
  and extended to nativesdk.

(From OE-Core rev: 50864df5b0eb3d1704e8fe75c06e957af0b41c38)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-devtools/python/python-testtools.inc

@@ -0,0 +1,27 @@
+SUMMARY = "Extensions to the Python standard library unit testing framework"
+HOMEPAGE = "https://pypi.python.org/pypi/testtools/"
+SECTION = "devel/python"
+LICENSE = "Apache-2.0"
+LIC_FILES_CHKSUM = "file://LICENSE;md5=e2c9d3e8ba7141c83bfef190e0b9379a"
+
+inherit pypi
+
+SRC_URI[md5sum] = "adef817b07ba24fd6d807fd41a4f1ef4"
+SRC_URI[sha256sum] = "80f606607a6e4ce4d0e24e5b786562aa42c581906f3c070607a4265f3da65810"
+
+DEPENDS += " \
+    ${PYTHON_PN}-pbr \
+    "
+
+# Satisfy setup.py 'setup_requires'
+DEPENDS += " \
+    ${PYTHON_PN}-pbr-native \
+    "
+
+RDEPENDS_${PN} += "\
+    ${PYTHON_PN}-extras \
+    ${PYTHON_PN}-pbr \
+    ${PYTHON_PN}-six \
+    "
+
+BBCLASSEXTEND = "nativesdk"