http.c: use strbuf API in quote_ref_url
http.c: use strbuf API in quote_ref_url

In addition, ''quote_ref_url'' inserts a slash between the base URL and
remote ref path only if needed. Previously, this insertion wasn't
contingent on the lack of a separating slash.

Signed-off-by: Tay Ray Chuan <781f23e367a7ada1fde54f9860fdd95ca652794e@gmail.com>
Acked-by: Johannes Schindelin <53fb8db7833fca1e1746dd8592f61048d350f64c@gmx.de>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git