Create jsondiff tool to capture diffs between two JSON expectations files.

tools/tests/rebaseline.sh

 #!/bin/bash
 
 # Rebaseline the skdiff/*/output-expected/ subdirectories used by the skdiff
 # self-tests, and similar for benchgraphs/*/output-expected.
 #
 # Use with caution: are you sure the new results are actually correct?
 #
 # YOU MUST RE-RUN THIS UNTIL THE SELF-TESTS SUCCEED!
 #
 # TODO: currently, this must be run on Linux to generate baselines that match
@@ skipping 62 matching lines @@
     svn rm $FILE
   done
 }
 
 
 # cd into the gm self-test dir
 cd $(dirname $0)
 
 ./run.sh
 SELFTEST_RESULT=$?
-SUBDIRS="skdiff benchgraphs rebaseline/output"
+SUBDIRS="skdiff benchgraphs rebaseline/output jsondiff/output"
 echo
 if [ "$SELFTEST_RESULT" != "0" ]; then
   for SUBDIR in $SUBDIRS; do
     replace_expected_with_actual $SUBDIR
   done
   echo "Self-tests still failing, you should probably run this again..."
 else
   for SUBDIR in $SUBDIRS; do
     svn_add_new_files $SUBDIR
     svn_delete_old_files $SUBDIR
   done
   echo "Self-tests succeeded this time, you should be done!"
 fi
 exit $SELFTEST_RESULT