Add ChangeLog

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

ChangeLog

+Version NEXT:
+0000-00-00 Maxime “pep” Buquet <pep@bouah.net>
+  * Improvements:
+    - Add more fine errors during plugin setup.
+    - Ensure variable is available when publish-options is not available. (!5)
+    - Don't just catch precondition-not-met, ensure the node is being
+      configured and published. Add logging.
+Version 0.3.0:
+2019-12-29 Maxime “pep” Buquet <pep@bouah.net>
+  * Breaking:
+    - Require lib omemo 0.11
+  * Improvements:
+    - Ensure correct types are passed to the omemo lib via expect_problems. (!3)
+    - Implement fallback on precondition-not-met when publishing devicelist (!2)
+      and bundle
+  * Changes:
+    - Support only from Python 3.7