+ add demo sido as submodule

.gitmodules

@@ -22,3 +22,6 @@
 [submodule "Assets/AddOns/vive"]
 	path = Assets/AddOns/vive
 	url = git@gitlab.inria.fr:crowdmp/addons/vive.git
+[submodule "Assets/Demo/SIDO"]
+	path = Assets/Demo/SIDO
+	url = git@gitlab.inria.fr:crowdmp/demo/sido.git

SIDO @ e401a918

+Subproject commit e401a918f6cb4c91ea9ab9e96403f22868ce697c

Assets/Demo/SIDO.meta

+fileFormatVersion: 2
+guid: da3e5b78f4289ee4fbb080d0a6fc989a
+folderAsset: yes
+timeCreated: 1555601153
+licenseType: Free
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: