/*
 * call-seq:
 *   easy.low_speed_limit = fixnum or nil        => fixnum or nil
 *
 * Set the transfer speed (in bytes per second) that the transfer should be
 * below during +low_speed_time+ seconds for the library to consider it too
 * slow and abort.
 */
static VALUE ruby_curl_easy_low_speed_limit_set(VALUE self, VALUE low_speed_limit) {