A number of small changes.
- install-required-gems installs platform-specifid gems smartly
- Logging indicates normal vs. exceptional termination
- Default log level is debug
- Pegged random generator so I can fix map generation
- Fixed user spawn location
- Log file clears every new run
Started on connect-the-unconnected: flood fill.
Refactoring: separate out dungeon tunneling code
Closer to connectivity: perimeters and connection