Support secure mode for csrf cookie (#7)

Options struct has Secure flag for csrf cookie, but it's just ignored
and corresponding argument of SetCookie() is hardcodded to false.

This pass Options.Secure to SetCookie in csrf.Generate()

Signed-off-by: Aleksandr Bulyshchenko <A.Bulyshchenko@globallogic.com>

csrf.go

@@ -222,7 +222,7 @@ func Generate(options ...Options) macaron.Handler {
 			// FIXME: actionId.
 			x.Token = GenerateToken(x.Secret, x.ID, "POST")
 			if opt.SetCookie {
-				ctx.SetCookie(opt.Cookie, x.Token, 0, opt.CookiePath, "", false, opt.CookieHttpOnly, time.Now().AddDate(0, 0, 1))
+				ctx.SetCookie(opt.Cookie, x.Token, 0, opt.CookiePath, "", opt.Secure, opt.CookieHttpOnly, time.Now().AddDate(0, 0, 1))
 			}
 		}