Update README.md

README.md

@@ -1,2 +1,20 @@
 # default-applications-tree
 
+You can add more application sections into applications-tree.json.
+You have to specify the application name and version. For example:
+
+        {
+            "name": "nextcloud",
+            "version": "latest"
+        }
+
+The name must be the same as the directory name of the application.
+
+The directory of an application have to contain a template.json file and can contain more json files (service, domain, secret, etc. files).
+
+The mandatory template.json file's structure is the following. 
+ - "name" - the name of the application, must be the same as the directory name
+ - "fields" - array of used variables by service
+
+
+