Import textures with texture compression off.
You can set EditorUserBuildSettings.overrideTextureCompression to ForceUncompressed to import
all textures into uncompressed texture formats. This is the same as if all the textures had "Compression: None"
option set in their import settings.
This setting is mostly useful for local development, to speed up texture importing or a platform
switch process. Some compressed texture formats are slow to compress, and for local development
you might want to skip that. Note however that uncompressed textures do take up more memory
and might be slower for GPU to render with.
Additional resources: EditorUserBuildSettings.overrideTextureCompression, Texture Importer, command line arguments.