Move error-stack text to top of usage display (#1564)

* Move error-stack text to top of usage display

* Add optional tag ti list

* format changes

* Revert incorrect change

tools/test/h5repack/testfiles/h5repack-help.txt

@@ -1,14 +1,15 @@
 usage: h5repack [OPTIONS] file1 file2
   file1                    Input HDF5 File
   file2                    Output HDF5 File
+  ERROR
+   --enable-error-stack    Prints messages from the HDF5 error stack as they occur.
+                           Optional value 2 also prints file open errors.
   OPTIONS
    -h, --help              Print a usage message and exit
    -v N, --verbose=N       Verbose mode, print object information.
       N - is an integer greater than 1, 2 displays read/write timing
    -V, --version           Print version number and exit
    -n, --native            Use a native HDF5 type when repacking
-   --enable-error-stack    Prints messages from the HDF5 error stack as they
-                           occur
    --src-vol-value         Value (ID) of the VOL connector to use for opening the
                            input HDF5 file specified
    --src-vol-name          Name of the VOL connector to use for opening the input