SCRIPTS: git-show-backports: list new commits and how to review them with -L

The new "-L" option is convenient for quick backport sessions, but it
doesn't list the commit subjects nor the review command. Let's just add
these to ease backport sessions. However we don't do it in quiet mode
(-q) because the output is sometimes parsed by automatic backport
scripts.

(cherry picked from commit 226bb4b)
Signed-off-by: Willy Tarreau <w@1wt.eu>

Author: wtarreau

scripts/git-show-backports

@@ -336,6 +336,16 @@ dump_commit_matrix | column -t | \
 	elif [ -n "$SINCELAST" ]; then
 		echo "Found ${#since_last[@]} commit(s) added to branch $REF since last backported commit $last_bkp:"
 		echo
+		if [ -z "$QUIET" ]; then
+			for c in "${since_last[@]}"; do
+				echo "$(git log -1 --pretty="  %h  | %s" "$c")"
+			done
+			echo
+			echo "In order to show and/or apply them all to current branch :"
+			echo
+			echo "   git show --pretty=format:'%C(yellow)commit  %H%C(normal)%nAuthor: %an <%ae>%nDate:   %aD%n%n%C(green)%C(bold)git cherry-pick -sx %h%n%n%w(0,4,4)%B%N' ${since_last[@]}"
+			echo
+		fi
 		echo "   git cherry-pick -sx ${since_last[@]}"
 		echo
 	elif [ -n "$MISSING" -a ${#left_commits[@]} -eq 0 ]; then