migrating synchronizer docs

Change-Id: Icab56e08edc8f6082194d9d10dc42f3efa16ad71
diff --git a/docs/SUMMARY.md b/docs/SUMMARY.md
index 6ea93b9..9944b2a 100644
--- a/docs/SUMMARY.md
+++ b/docs/SUMMARY.md
@@ -14,11 +14,13 @@
     * [Configuring XOS: xosconfig](xos/modules/xosconfig.md)
     * [Powering Up a POD](operate/power_up.md)
     * [ELK Stack Logs](operate/elk_stack.md)
-* [Models for CORD](xos/README.md)
-    * [Defining Models: xproto](xos/dev/xproto.md)
+* [Defining Models in CORD](xos/README.md)
+    * [XOS Support for Models](xos/dev/xproto.md)
     * [Core Models](xos/core_models.md)
     * [Security Policies](xos/security_policies.md)
-    * [Modeling Conventions](xos/modeling_conventions.md)
+    * [Writing Synchronizers](xos/dev/synchronizers.md)
+        * [Design Guidelines](xos/dev/sync_arch.md)
+        * [Implementation Details](xos/dev/sync_impl.md)
 * [Developing for CORD](develop.md)
     * [Workflow: platform-install](platform-install/README.md)
     * [Workflow: local dev](xos/dev/local_env.md)