Infer rootwrap arguments from project

We can infer the binary and configuration paths just from the project
name and expanding this to the known *_DIR & *_BIN_DIR variables.  A
similar thing is done for policyd settings

Change-Id: I7c6a9fa106948ae5cbcf52555ade6154623798f1
diff --git a/lib/cinder b/lib/cinder
index eb0e1d7..3c5425a 100644
--- a/lib/cinder
+++ b/lib/cinder
@@ -190,7 +190,7 @@
 
     rm -f $CINDER_CONF
 
-    configure_rootwrap cinder $CINDER_BIN_DIR/cinder-rootwrap $CINDER_DIR/etc/cinder
+    configure_rootwrap cinder
 
     cp $CINDER_DIR/etc/cinder/api-paste.ini $CINDER_API_PASTE_INI