router now uses STL again, no limits on number of sessions per channel
moved router and associated classes to asiodnp3
physical layer callbacks no longer share interfaces with dnp3 layer stuff
tweaked the layer definitions
Moved layer definitions from openpal to opendnp3
simplified linkroute
Renamed LinkRoute -> Route. Moved to base directory
Merge branch 'addressrefactor' of github.com:automatak/dnp3 into addressrefactor