Guide for installing Tensorflow-GPU in WSL2

[Avditvs]

Added instructions enabling the use of CUDA acceleration inside Windows Subsystem for Linux 2.

[lamberta]

Thanks, @Avditvs , this is cool.

Unfortunately, since this is not an officially supported target we can't commit to maintaining this section.

@angerson Is this something that could live under SIG BUILD?

[angerson]

Yeah, this could go under Build, certainly. The other lead and are just now rearranging the folders to fit our rearrangement proposal (tensorflow/build#16), so something like this would be a welcome new addition to test it out.

[lamberta]

Sounds good, thanks @angerson

@Avditvs Can you submit this PR to the SIG Build repo, please? https://github.com/tensorflow/build
They have a public mailing list if you want to discuss. Closing this PR.