Added isReaderOpen method.

Change-Id: Ia084d1a9c75755dfb6cacb96310caa8665aab209
diff --git a/Changes b/Changes
index 5d2a9c6..68caaa5 100644
--- a/Changes
+++ b/Changes
@@ -1,4 +1,4 @@
-0.58.5 2019-03-15
+0.58.5 2019-03-18
     - [bugfix] Fix bug where duplicate keys occured in
       field data output (diewald)
     - [bugfix] Fix bug where fields already set where lifted
@@ -14,6 +14,7 @@
     - [bugfix] Fixed #53 element distance query bug (margaretha)
     - [bugfix] Workaround for #54 failing offsets due to
       surrogate pairs (diewald)
+    - Added isReaderOpen method (margaretha)
 
 0.58.4 2019-02-05
     - [cleanup] Remove deprecated methods setLicense/getLicense,