Renamed and moved a few things

address assignment -> dhcp relay
community -> resource

Change-Id: I807a896d8a8f610eb8af0063ba36ba0f0d55c070
diff --git a/index.rst b/index.rst
index d42d416..1eeef1d 100644
--- a/index.rst
+++ b/index.rst
@@ -13,5 +13,5 @@
    configuration
    troubleshooting
    testing
-   community
+   resource
    readme