Clean up all file-defines and remove all tabs

Socket/Protocols: Move incorrectly placed members from AddressableBSDSocketProtocol to BSDSocketProtocol
Socket/Protocols: Add missing DatagramSocketProtocol to some protocols
Socket/Protocols: Extend documentation of addressing classes

Adjust all senf components to use Utils/Tags.hh (if necessary)

Rename IpV[46]* -> IPv[46]*

Utils: Rename SafeBool to safe_bool (hmm ...)

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

Socket/Protocols/Inet: Remove not implemented  async resolv constructors (in favor of a later non-member implementation)
Socket/Protocols/Inet: More detailed exceptions thrown by INet4Address / INet6Address

Socket/Protocols/INet: Implement INet6Network

Socket/Protocols/INet: More complete CheckINet6Address documentation

Socket/Protocols/Inet: Update INet6SocketAddress syntax to support hostnames and correct zone-id syntax

Socket/Protocols/INet: Add INet4Address documentation
Fix some missed INet4Address -> INet4SocketAddress renames
Fixed several std:string arguments to use std::string const &