In request and response buckets, replace usages of sprintf

* buckets/request_buckets.c
  (serialize_data): change to snprintf
* buckets/response_buckets.c
  (serf_bucket_outgoing_response_prepare,
  serialize_outgoing_response): same



git-svn-id: https://svn.apache.org/repos/asf/serf/trunk@1717352 13f79535-47bb-0310-9956-ffa450edef68
2 files changed