Gradio update

[shahbuland]

Changes:

General:

• Gradio now has a separate ClientManager that can be enabled by setting a flag on the master CHEESE object

Gradio Scalability:

• Previously created many demos, one per client. This is extremely inefficient
• Now one demo that many users can connect to with different credentials
• All examples have been updated to follow new Gradio setup
• Creating UI is now even simpler

Authentication and user tracking:

• Users now have to login before they can begin labelling data
• Batch elements now intrinsically store the ID of the last client that labelled them
• Users can flag data as being erroneous

QOL

• Previously user would have to submit empty task to receive their first real task
• This has been fixed and task + data now present immediately after login
• Some old imports that are now redundant were causing errors on previous examples. These have been fixed.
• Examples are now even shorter and hopefully simpler