* swarm: Added lightnode flag

Added --lightnode command line parameter
Added LightNode to Handshake message

* swarm/config: Fixed variable naming

* cmd/swarm: Changed BoolTFlag to BoolFlag for SwarmLightNodeEnabled

* swarm/network: Changed logging

* swarm/network: Changed protocol version testing

* swarm/network: Renamed DefaultNetworkID variable to TestProtocolNetworkID

* swarm/network: Bumped protocol version

* swarm/network: Changed LightNode handhsake test to table driven

* swarm/network: Changed back TestProtocolVersion to 5 for now

* swarm/network: Moved the test configuration inside the test function scope