Documentation: clarify quoting in gitignore docs
An asterisk in "Documentation/*.txt" quoted with \ to avoid bold text
is being output as \* because asciidoc does not consider it a
candidate for escaping (there is no matching * to pair it with).
So the manual looks like it is saying that one should write
"Documentation/\*.txt" in the .gitignore file.
Reported-by: Frédéric Brière <fbriere@fbriere.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>