README file

- added disclaimer about the risk with using a dev branch.

README

@@ -1,3 +1,18 @@
+                         *** Disclaimer ***
+                       *** during ongoing ***
+                        *** development ***
+
+The development branch is a work in progress and may not pass all quality
+tests, therefore it may harm your data. While we welcome bug reports from
+the development branch, we do not guarantee proper or timely fixes.
+
+      Broken functionality may arise from ongoing development work.
+
+                        Make proper backups.
+
+       Be aware that using the development branch involves risks.
+
+---
 
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