#68, #59: Add a section for Confluence Data Center to README

README.MD

@@ -23,6 +23,11 @@ Install via [Atlassian Marketplace](https://marketplace.atlassian.com/plugins/co
 A detailed description of the available configuration fields and usage is described in
 the [Wiki...](https://github.com/baloise/digital-signature/wiki/Signature-Macro-Usage)
 
+## Using Confluence Data Center Version
+Digital-signature can be used on Confluence Data Center, however it is not yet officially tested and approved.
+When performing an update you might have to invalidate the plugin cache and restart Confluence. For details refer
+to [#68](https://github.com/baloise/digital-signature/issues/68).
+
 ## Feature overview
 ### Insert / edit macro
 ![](./docs/img/contract_text.png)