Documentation: remove stray backslash from "git bundle" manual

In v1.6.2.2~6^2~4 (Documentation: minor grammatical fixes
and rewording in git-bundle.txt, 2009-03-22), backslashes were
introduced before ~ to avoid introducing unintentional
superscripts.  In one paragraph there is only one ~, though,
making that not a candidate for quoting, and asciidoc 8.5.8
passes the backslash through so the man page says "\~10..master".

Maybe there is an asciidoc behavior change involved.

In any case, we should replace tildes with a {tilde} entity which
means the same thing regardless of where it is found.

Reported-by: Frédéric Brière <fbriere@fbriere.net>
Cc: David J. Mellor <dmellor@whistlingcat.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-bundle.txt

@@ -60,7 +60,7 @@ unbundle <file>::
 [git-rev-list-args...]::
        A list of arguments, acceptable to 'git rev-parse' and
        'git rev-list', that specifies the specific objects and references
-       to transport.  For example, `master\~10..master` causes the
+       to transport.  For example, `master~10..master` causes the
        current master reference to be packaged along with all objects
        added since its 10th ancestor commit.  There is no explicit
        limit to the number of references and objects that may be
@@ -79,12 +79,12 @@ SPECIFYING REFERENCES
 
 'git bundle' will only package references that are shown by
 'git show-ref': this includes heads, tags, and remote heads.  References
-such as `master\~1` cannot be packaged, but are perfectly suitable for
+such as `master{tilde}1` cannot be packaged, but are perfectly suitable for
 defining the basis.  More than one reference may be packaged, and more
 than one basis can be specified.  The objects packaged are those not
 contained in the union of the given bases.  Each basis can be
-specified explicitly (e.g. `^master\~10`), or implicitly (e.g.
-`master\~10..master`, `--since=10.days.ago master`).
+specified explicitly (e.g. `^master{tilde}10`), or implicitly (e.g.
+`master{tilde}10..master`, `--since=10.days.ago master`).
 
 It is very important that the basis used be held by the destination.
 It is okay to err on the side of caution, causing the bundle file