face restoration and tiling moved to settings - use "Options in main UI" setting if you want them back

split shared.py into multiple files; should resolve all circular reference import errors related to shared.py

- correctly read values from pasted infotext
- setting for column count
- infotext paste: do not add a field to override settings if some other component is already handling it

- the setting for preferring opts.sd_vae has been inverted and reworded
- resolve_vae function made easier to read and now returns an object rather than a tuple
- if the checkbox for overriding per-model preferences is checked, opts.sd_vae overrides checkpoint user metadata
- changing VAE in user metadata  for currently loaded model immediately applies the selection

add NV option for Random number generator source setting, which allows to generate same pictures on CPU/AMD/Mac as on NVidia  videocards.

add backwards compatibility --lyco-dir-backcompat option, use that for LyCORIS directory instead of hardcoded value
prevent running preload.py for disabled extensions