Bump xos libraries to version 4.0.0

Change-Id: If2cd9948426956a237e5ab65c3cfb724966bf521
diff --git a/xos/synchronizer/config.yaml b/xos/synchronizer/config.yaml
index 28f3f95..048705c 100644
--- a/xos/synchronizer/config.yaml
+++ b/xos/synchronizer/config.yaml
@@ -15,7 +15,7 @@
 
 
 name: fabric
-core_version: ">=3.2.8"
+core_version: ">=4.0.0"
 required_models:
   - FabricService
 steps_dir: "/opt/xos/synchronizers/fabric/steps"