Version numbers in asciidoc-generated content (such as man pages)
went missing as of da8a366 (Documentation: refactor common operations
into variables). Fix by putting the underscore back in the variable
name.
Signed-off-by: Sven van Haastregt <svenvh@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>