SSL update from the "ssl" branch at SourceForge

SSL update from the "ssl" branch at SourceForge

* Several SSL tweaking options
  - SSL version per https_port, no longer a global setting
  - supported chipers, per https_port
  - supported protocols, per https_port
  - connection shutdown method

* Fix the bug reported by Noel Burton-Krahn where SSL connections
  could get hung with data pending in the SSL internal buffers. Mostly
  seen on large POST/PUT requests, but could in theory appear on any
  request larger than 4K.