[Feature request] Conversion between DDS and VTF, without reencoding

[SirYodaJedi]

The DDS file format supports all of the same image formats as VTF (plus more), so there should be an option when importing a DDS file to retain source format or something along those lines (as long as the source DDS uses a compatible format and is a power of 2). Such an option would copy the image data and any mipmaps over to a VTF file (and create thumbnails, info resources, etc. if the user requests), while avoiding introducing green tint to DXTn or BGR565 textures and other lossy conversion issues.

Additionally, there could be an option to export as DDS, using the same image format as the source VTF.

I'm pretty sure this would be possible; while I am not familiar with the nitty gritty, I'd imagine that the image data itself can just be copied over, since both file formats encode the image using little endian with the same image formats designed for the GPU.