fw: rename BroadcastStrategy to MulticastStrategy

BroadcastStrategy is temporarily retained for backwards compatibility.

This commit also updates nfd.conf and ndn-autoconfig to use MulticastStrategy
in place of BroadcastStrategy.

refs #3011

Change-Id: I011f1cf75db26b3c93552f8322a0bba4ce8dd033
diff --git a/docs/manpages/nfdc.rst b/docs/manpages/nfdc.rst
index 9da47db..af6764b 100644
--- a/docs/manpages/nfdc.rst
+++ b/docs/manpages/nfdc.rst
@@ -119,9 +119,10 @@
         Currently, NFD supports the following strategies::
 
             ndn:/localhost/nfd/strategy/best-route
-            ndn:/localhost/nfd/strategy/broadcast
+            ndn:/localhost/nfd/strategy/multicast
             ndn:/localhost/nfd/strategy/client-control
             ndn:/localhost/nfd/strategy/ncc
+            ndn:/localhost/nfd/strategy/access
 
   ``unset-strategy``
     Unset the strategy for a given ``namespace``.