patch 9.1.1009: diff feature can be improved

Problem:  diff feature can be improved
Solution: include the linematch diff alignment algorithm
          (Jonathon)

closes: #9661

Signed-off-by: Jonathon <jonathonwhite@protonmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/dumps/Test_diff_24.dump b/src/testdir/dumps/Test_diff_24.dump
new file mode 100644
index 0000000..71004bd
--- /dev/null
+++ b/src/testdir/dumps/Test_diff_24.dump
@@ -0,0 +1,20 @@
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