idgames_file_map.pl: count total number of API requests made

- Check total number of requests made against number of requests for
  debugging via --debug-requests
- Added more debug output
- Fixed setting of the number of API requests to make when debugging
- Use File::Basename::basename in log output and for HTTP user agent
- Added more script examples
File: finished adding attributes, added populate() method
JSONParser: added parsing_module attribute

- Renamed the variable holding parsed content
XMLParser: added parsing_module attribute

- Renamed the variable holding parsed content