Add release notes for tools

release_docs/RELEASE.txt

@@ -659,7 +659,7 @@ Bug Fixes since HDF5-1.10.3 release
     - Fixed the segmentation fault when reading attributes with multiple threads
 
       It was reported that the reading of attributes with variable length string
-      datatype will crash with segmentation fault particularly when the number of 
+      datatype will crash with segmentation fault particularly when the number of
       threads is high (>16 threads).  The problem was due to the file pointer that
       was set in the variable length string datatype for the attribute.  That file
       pointer was already closed when the attribute was accessed.
@@ -1028,7 +1028,43 @@ Bug Fixes since HDF5-1.10.3 release
 
     Tools
     -----
-    -
+    - The tools library was updated by standardizing the error stack process.
+
+      General sequence is:
+          h5tools_setprogname(PROGRAMNAME);
+          h5tools_setstatus(EXIT_SUCCESS);
+          h5tools_init();
+          ... process the command-line (check for error-stack enable) ...
+          h5tools_error_report();
+          ... (do work) ...
+          h5diff_exit(ret);
+
+      (ADB - 2020/07/20, HDFFV-11066)
+
+    - h5diff fixed a command line parsing error.
+
+      h5diff would ignore the argument to -d (delta) if it is smaller than DBL_EPSILON.
+      The macro H5_DBL_ABS_EQUAL was removed and a direct value comparision was used.
+
+      (ADB - 2020/07/20, HDFFV-10897)
+
+    - h5diff added a command line option to ignore attributes.
+
+      h5diff would ignore all objects with a supplied path if the exclude-path argument is used.
+      Adding the exclude-attribute argument will only eclude attributes, with the supplied path,
+      from comparision.
+
+      (ADB - 2020/07/20, HDFFV-5935)
+
+    - h5diff added another level to the verbose argument to print filenames.
+
+      Added verbose level 3 that is level 2 plus the filenames. The levels are:
+          0 : Identical to '-v' or '--verbose'
+          1 : All level 0 information plus one-line attribute status summary
+          2 : All level 1 information plus extended attribute status report
+          3 : All level 2 information plus file names
+
+      (ADB - 2020/07/20, HDFFV-10005)
 
     High-Level APIs:
     ------