* modules/ssl/ssl_engine_io.c: Revamp output buffering: add a

  "coalesce" filter which buffers the plaintext, and remove buffering
  of the SSL records -- i.e. buffer before the SSL output filter,
  rather than after it.  This aims to reduce the network overhead
  imposed by the output of many small brigades (such as produced by
  chunked HTTP response), which can now be transformed into a few
  large TLS records rather than many small ones.

  (ssl_filter_ctx_t): Remove "nobuffer" field.
  (bio_filter_out_ctx_t): Remove length, buffer, blen fields.
  (bio_filter_out_pass): Split from bio_filter_out_flush.
  (bio_filter_out_write): Remove handling of buffer.
  (bio_filter_out_ctrl): Adjust to reflect lack of buffer.
  (ssl_io_filter_coalesce): Add new filter...
  (ssl_io_filter_init): ...add it to the filter chain...
  (ssl_io_filter_register): ...and register it.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1059910 13f79535-47bb-0310-9956-ffa450edef68