Documentation: fix section header mark-up

Asciidoctor is stricter than AsciiDoc when deciding if underlining is a section title or the start of preformatted text. Make the length of the underlining match the text to ensure that it renders correctly in all implementations. Signed-off-by: John Keeping <john@keeping.me.uk> [jc: squashed in git-bisect one noticed by Michael J Gruber] Signed-off-by: Junio C Hamano <gitster@pobox.com>

John Keeping committed Sep 25, 2015 at 13:59 UTC be510e0105eaed87dca76fd71f13e22952640599
2 files changed +2 -2
Documentation/git-bisect-lk2009.txt
+1 -1
@@ -1321,7 +1321,7 @@ So git bisect is unconditional goodness - and feel free to quote that
1321 _____________
1322
1323 Acknowledgments
1324 -----------------
1324 +---------------
1325
1326 Many thanks to Junio Hamano for his help in reviewing this paper, for
1327 reviewing the patches I sent to the Git mailing list, for discussing
Documentation/user-manual.txt
+1 -1
@@ -3424,7 +3424,7 @@ just missing one particular blob version.
3424
3425 [[the-index]]
3426 The index
3427 ------------
3427 +---------
3428
3429 The index is a binary file (generally kept in `.git/index`) containing a
3430 sorted list of path names, each with permissions and the SHA-1 of a blob