- fixes errors introduced in the earlier refactoring
- more variables moved to state.py
- path finding functions moved to paths.py
- remembers IPv6 network unreachable (in the future can be used to skip
IPv6 for a while)
- got rid of shared config parser and made it into a singleton
- refactored safeConfigGetBoolean as a method of the config singleton
- refactored safeConfigGet as a method of the config singleton
- moved softwareVersion from shared.py into version.py
- moved some global variables from shared.py into state.py
- moved some protocol-specific functions from shared.py into protocol.py
