Very basic configuration stuff

- Comment out d_main system stuff we don't use.
- Have Python's GC check for uncollectable objects during startup.
- Change NOIWADMSG to reflect the new configuration format.
- Configuration module using ConfigParser.
- Moved ReportFatalError to console setup, moved BaseFileSearch to a new
paths module.
- Pass the file name, not the full path, to the IWAD Picker.