http/ftp: optionally ask curl to not use EPSV command

If http.noEPSV config variable is defined and true, or if
GIT_CURL_FTP_NO_EPSV environment variable is defined, disable using
of EPSV ftp command (PASV will be used instead). This is helpful with
some "poor" ftp servers which does not support EPSV mode.

Signed-off-by: Sasha Khapyorsky <sashak@voltaire.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

git-ls-remote.sh

diff --git a/git-ls-remote.sh b/git-ls-remote.sh
index 2c0b521..0f88953 100755
--- a/git-ls-remote.sh
+++ b/git-ls-remote.sh
@@ -53,6 +53,10 @@
         if [ -n "$GIT_SSL_NO_VERIFY" ]; then
             curl_extra_args="-k"
         fi
+	if [ -n "$GIT_CURL_FTP_NO_EPSV" -o \
+		"`git-repo-config --bool http.noEPSV`" = true ]; then
+		curl_extra_args="${curl_extra_args} --disable-epsv"
+	fi
 	curl -nsf $curl_extra_args --header "Pragma: no-cache" "$peek_repo/info/refs" ||
 		echo "failed	slurping"
 	;;