completion: simplify __git_remotes()

The __git_remotes() helper function lists the remotes from the config
file by processing the output of a 'git config' query.  A simple 'git
remote' produces the exact same output, so run that instead.

Remotes under '$GIT_DIR/remotes' are still listed by running 'ls -1',
because 'git remote' unfortunately ignores them.

Signed-off-by: SZEDER Gábor <szeder@ira.uka.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

contrib/completion/git-completion.bash

@@ -411,12 +411,9 @@ __git_refs_remotes ()
 
 __git_remotes ()
 {
-	local i IFS=$'\n' d="$(__gitdir)"
+	local d="$(__gitdir)"
 	test -d "$d/remotes" && ls -1 "$d/remotes"
-	for i in $(git --git-dir="$d" config --get-regexp 'remote\..*\.url' 2>/dev/null); do
-		i="${i#remote.}"
-		echo "${i/.url*/}"
-	done
+	git --git-dir="$d" remote
 }
 
 __git_list_merge_strategies ()