Add error handling to window and helper script

[KINGTUT10101]

• Added error handling to GUI.py so the app will show an error window pop-up instead of closing without notice
  • Errors will also be written to the in-app console
• Added a helper script to the file shuffler folder that will help identify bad data in files
  • The script will find non-csv files that may be polluting the data
  • The script will also count the total number of columns in each file in a directory. This can ensure that each file contains the same types of data
• Set the default window size to something much more sensible
  • The window is also not fullscreen by default anymore

[3C-SCSU]

Code improvement and added features. No conflicts.