Replace all 'throw SystemException(...)' commands with 'throwErrno(...)'
Add additional links to documentation header

Provide additional include files for socket protocols
Socket: Change UDP socket handle to bind instead of connect if given an address argument.

Make all include path's relative
Add 'senf/Packets.hh', 'senf/PPI.hh' and 'senf/Socket.hh'

Unified emacs Local Variables

Renaned directory satscons to senfscons

add missing retrive_filehandle overload
fix operator bool (use safe bool idiom)
add GenericSockAddr as default Address implementation

Implemented EAGAIN / EWOULDBLOCK and EINTR handling
Made the generic connect implementation always block
Implemented SocketHandle::state() infrastructure

added listen to ConnectedCommunicationPolicy
added primitive doxygen documentation
cleaned up naming of some files
fixed INetProtocol.cc (missing const modifiers)
removed SocketProtcolHelper in favor of directly inheriting SocketProtocol virtually
moved implementation of TCPv4SocketProtocol virtual methods into the base classes
added rudimentary testing of the TCPv4SocketHandle protocol interface
finalized PacketSocketHandle

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