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/release/repolist.rst b/docs/release/repolist.rst
index ba1bd6a..d807ed8 100644
--- a/docs/release/repolist.rst
+++ b/docs/release/repolist.rst
@@ -75,3 +75,4 @@
    externalapi/nbi <../submodules/externalapi/nbi.git/docs/index>
    music/distributed-kv-store <../submodules/music/distributed-kv-store.git/docs/index>
    vnfrqts/testcases <../submodules/vnfrqts/testcases.git/docs/index>
+   vnfrqts/usecases <../submodules/vnfrqts/usecases.git/docs/index>