xos-sample-gui-extension cleanup and update with new documentation

Change-Id: I6b70f5127ea631cfdd1f8a372a51c20f547e9c44
diff --git a/xos-sample-gui-extension.yaml b/xos-sample-gui-extension.yaml
index 798230e..36f7ec1 100644
--- a/xos-sample-gui-extension.yaml
+++ b/xos-sample-gui-extension.yaml
@@ -16,7 +16,7 @@
 
 tosca_definitions_version: tosca_simple_yaml_1_0
 
-description: Persiste xos-sample-gui-extension
+description: xos-sample-gui-extension
 
 imports:
    - custom_types/xos.yaml
@@ -28,4 +28,4 @@
     xos-sample-gui-extension:
       type: tosca.nodes.XOSGuiExtension
       properties:
-        files: /spa/extensions/xos-sample-gui-extension/vendor.js, /spa/extensions/xos-sample-gui-extension/app.js
+        files: /xos/extensions/xos-sample-gui-extension/vendor.js, /xos/extensions/xos-sample-gui-extension/app.js