DOC added vnfrqts/usecases

Adding VNF Requirements Use Cases project
This should be the same level as the VNF Requirements and VNF Guidelines projects
Followed this guide http://onap.readthedocs.io/en/latest/guides/onap-developer/how-to-use-docs/include-documentation.html#setup-project-repositories-s

Issue-ID: VNFRQTS-154

Change-Id: If9205dd4c533944085af639af413141a8ee0db88
Signed-off-by: Bozawglanian, Hagop (hb755d) <hb755d@att.com>
diff --git a/docs/guides/onap-user/vnfprovider.rst b/docs/guides/onap-user/vnfprovider.rst
index 469f2fc..413f7e7 100644
--- a/docs/guides/onap-user/vnfprovider.rst
+++ b/docs/guides/onap-user/vnfprovider.rst
@@ -10,3 +10,4 @@
    ../../../submodules/vnfrqts/guidelines.git/docs/index.rst
    ../../../submodules/vnfrqts/requirements.git/docs/index.rst
    ../../../submodules/vnfrqts/testcases.git/docs/index.rst
+   ../../../submodules/vnfrqts/usecases.git/docs/index.rst