git-rm.txt: Fix quoting

Literal " produces typographically incorrect quotations, but "works" in
most circumstances. In the subheadings of git-rm.txt, it "works" for the
html backend but not for the docbook conversion to nroff: double "" and
spurious double spaces appear in the output.

Replace "incorrect" quotations by ``correct'' ones, and fix other
"quotations" which are really `code fragments`.

This should make git-rm.txt "-clean.

Reported-by: Jeff King <peff@peff.net>
Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Helped-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-rm.txt

@@ -89,17 +89,17 @@ the paths that have disappeared from the filesystem. However,
 depending on the use case, there are several ways that can be
 done.
 
-Using "git commit -a"
-~~~~~~~~~~~~~~~~~~~~~
+Using ``git commit -a''
+~~~~~~~~~~~~~~~~~~~~~~~
 If you intend that your next commit should record all modifications
 of tracked files in the working tree and record all removals of
 files that have been removed from the working tree with `rm`
 (as opposed to `git rm`), use `git commit -a`, as it will
 automatically notice and record all removals.  You can also have a
 similar effect without committing by using `git add -u`.
 
-Using "git add -A"
-~~~~~~~~~~~~~~~~~~
+Using ``git add -A''
+~~~~~~~~~~~~~~~~~~~~
 When accepting a new code drop for a vendor branch, you probably
 want to record both the removal of paths and additions of new paths
 as well as modifications of existing paths.
@@ -111,8 +111,8 @@ tree using this command:
 git ls-files -z | xargs -0 rm -f
 ----------------
 
-and then "untar" the new code in the working tree. Alternately
-you could "rsync" the changes into the working tree.
+and then untar the new code in the working tree. Alternately
+you could 'rsync' the changes into the working tree.
 
 After that, the easiest way to record all removals, additions, and
 modifications in the working tree is: