PPI: Add boolean test for debug modules

PPI: Fix PassivePackeSink: provide front() instead of back() members
PPI: Provide specializations for void-argument callbacks in Events and Route
PPI: Add notifyThrottle/notifyUnthrottle to EventDescriptor
PPI: Re-implement routing classes using a traits-based implementation
PPI: Add Route unit testing (mainly testing throttling)

PPI: Implement throttling
PPI: Implement ModuleManager and ppi::init
PPI: Implement ThresholdQueuing
PPI: Hugely extended routing classes

PPI: Add RateStuffer image to documentation

PPI: Some small bugfixes to make ppitest work (not only compile :-) )
PPI: Add DebugModules

Socket/Protocols/INet: Slightly optimized generic INet6Address algorithms
Utils: Add ios_all_saver to hexdump()
senfscons: Add automatic image-copy to Doxygen builder (fixes weird doxygen copy problem)
Socket/Protocols/Inet: Add ConnectedUDPSocketHandle

Socket/Protocols/INet: Implement INet6Network

Socket/Protocols/INet: More complete CheckINet6Address documentation

Socket/Protocols/INet: Add optional resolve-type argument to INet6 adressing classes to support IpV4 mapped addresses
Socket/Protocols/INet: removed obsolte INet6SocketAddress constructor

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

Examples/Sniffer: Add 'interface' command line argument

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