Added changelog entry about renaming add_data_layer to add_table_layer

CHANGES.rst

@@ -5,7 +5,8 @@
   to table attributes. [#183]
 
 - Removed ``load_fits_data`` and added ``layers.add_image_layer`` instead,
-  which provides control over the image stretch. [#188]
+  which provides control over the image stretch, and renamed
+  ``layers.add_data_layer`` to ``layers.add_table_layer``. [#188]
 
 0.5.3 (2019-01-16)
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