rebase -i: Improve consistency of commit count in generated commit messages

Use the numeral "2" instead of the word "two" when two commits are
being interactively squashed.  This makes the treatment consistent
with that for higher numbers of commits.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-rebase--interactive.sh

@@ -360,7 +360,7 @@ make_squash_message () {
 		}' <"$SQUASH_MSG"
 	else
 		COUNT=2
-		echo "# This is a combination of two commits."
+		echo "# This is a combination of 2 commits."
 		echo "# The first commit's message is:"
 		echo
 		git cat-file commit HEAD | sed -e '1,/^$/d'

t/t3404-rebase-interactive.sh

@@ -135,7 +135,7 @@ test_expect_success 'squash' '
 	test_tick &&
 	GIT_AUTHOR_NAME="Nitfol" git commit -m "nitfol" file7 &&
 	echo "******************************" &&
-	FAKE_LINES="1 squash 2" EXPECT_HEADER_COUNT=two \
+	FAKE_LINES="1 squash 2" EXPECT_HEADER_COUNT=2 \
 		git rebase -i --onto master HEAD~2 &&
 	test B = $(cat file7) &&
 	test $(git rev-parse HEAD^) = $(git rev-parse master)
@@ -301,7 +301,7 @@ test_expect_success 'squash works as expected' '
 		git commit -m $n
 	done &&
 	one=$(git rev-parse HEAD~3) &&
-	FAKE_LINES="1 squash 3 2" EXPECT_HEADER_COUNT=two \
+	FAKE_LINES="1 squash 3 2" EXPECT_HEADER_COUNT=2 \
 		git rebase -i HEAD~3 &&
 	test $one = $(git rev-parse HEAD~2)
 '