Added error messages to unsupported queries in SpanAttributeQuery

Change-Id: I5481e99269be8de1246533d3b6b3532d2c45ae3f
diff --git a/Changes b/Changes
index 5724b9c..cc5c464 100644
--- a/Changes
+++ b/Changes
@@ -1,10 +1,12 @@
-0.59.7 2021-12-01
+0.60 2021-12-03
     - [feature] Implemented a new cache with on disk
       storage and auto-update (margaretha).
     - [feature] Support for tokenized snippet output
       (fixed #72; diewald)
+    - [cleanup] Added error messages to unsupported queries in 
+      SpanAttributeQuery (margaretha) 
 
-0.59.6 
+0.59.6 2021-11-10
     - [bugfix] Fixed skipping of focus spans (fixed #78; margaretha,
       diewald)
     - [bugfix] Clear matchlist if skip fails in NextSpans