Update README.md

add links to additional orgs and OneDM

events/2020.06.Online/TDs/README.md

@@ -11,7 +11,15 @@ identify things in data collection CSV files.
 * [Intel](Intel/README.md)
 * [Oracle](Oracle/README.md)
 * [Hitachi](Hitachi/README.md)
+* [TUM](TUM/README.md)
+* [Motius](Motius/README.md)
+* [Siemens](Siemens/README.md)
 
 Whether or not a Thing is active and online should be indicated in the [`active.csv`](active.csv) file.
 It is fine to submit a TD even if it is not running; simply indicate the Thing is inactive to avoid
 having people waste time trying to test against it.
+
+If you want to experiment with OneDM semantic annotation,
+see [here](https://github.com/one-data-model/playground/tree/master/sdfObject).
+[An example TD is here](https://github.com/mjkoster/ODM-Examples/blob/master/examples/switch-td.json).
+