Resolve "fix(io): nfiti files are not handled properly"
Description
The ITK reader can now be used multiple times.
Extra changes
Some minor errors were fixed in SightViewer about the ITK reader configuration. Nifti files are now the default proposed extension, since it will be more frequently used than "*.inr.gz" files.
Closes #905 (closed)
How to test it?
- Load an image, whatever format.
- Load another image through ITK Nifti reader.
- Confirm it does update the textures.