Changes to GUI - Add computer name field

[farnworthz-tqt]

Is your feature request related to a problem? Please describe.
Can't easily add the computer name in before you press the start button, would need this to be passed as a variable to the Unattend file though.

Describe the solution you'd like
A computer name field in the GUI so we can just add the name there as we still need to do this manually.

Describe alternatives you've considered
A prompt can be made in Unattend file but this isn't practical as we can't wait for it to get to that point.

Additional context
Would really appreciate this addition to the GUI.

Thanks

[farnworthz-tqt]

Any help would be greatly appreciated 👍 @OSDeploy