Implement way of distributing CUDA-powered application without requirement to have whole CUDA toolkit installed

Currently I can only compile CUDA file to `cubin` using `pycuda.compiler.compile()` for specific real architecture and then load it using `pycuda.driver.module_from_buffer()`.

AFAIK to distribute CUDA file without compiler/CUDA toolkit I need to either generate `cubin`-s for fixed set of architectures, and/or to generate `ptx` file, that can be assemblied by driver.

It would be nice if PyCUDA will provide some infrastructure for generating, storing and loading `cubin`/`ptx`, so that it would be possible to distribute CUDA-powered applications without CUDA toolkit/compiler.