Merged revisions 570-575,577-578 via svnmerge from

https://svn.berlios.de/svnroot/repos/senf/branches/socket-cleanup

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  r573 | g0dil | 2007-12-18 12:15:23 +0100 (Tue, 18 Dec 2007) | 6 lines
  
  Socket: Replace 'SocketProtocol::body()' member with 'fh()' and 'fd()' members
  Socket: Rename ConvertibleString to StreamableString and use 'operator<<' instead of 'operator='
  Socket: some minor documentation clarifications
  Socket/Protocols/UN: Removed unneeded UNAddress
  Socket/Protocols/UN: Fixed UNSocketAddress to adhere to the GenericAddressingPolicy requirements
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  r577 | g0dil | 2007-12-18 13:08:27 +0100 (Tue, 18 Dec 2007) | 1 line
  
  Socket/Protocols/UN: Add all_includes.hh to svn:ignore
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