Fixes several files incorrectly stated a different license from the actual project, as well as the copyright headers included in all files. This change has no effect on the licensing terms, it should clear up a bit of confusion by contributors. Plus the files get a bit smaller, and we have less duplicated information across the entire project.
Overall the project is GPLv2 if not built with Qt, and GPLv3 if it is built with Qt. There are no parts licensed under a different license, all have been adapted from other compatible licenses into GPLv2 or GPLv3.
The CUDA library is always available as a singleton, so it does not make sense for it to be passed in. Instead we can simply grab it from the singleton and use it as it is, which makes the code easier to maintain and automates certain code.
Due to the 'nvcuda' library being part of the driver, it falls in a clause of the GPL which allows us to load and interface with system drivers. Since we can't rely on Nvidias headers here (incompatible license), most of this was pulled from FFmpeg and other things were found out via testing.
