Modify Docker section in Readme

Hello,

I should have known this from the start, but the readme on this repo is unclear when it comes to docker. I read the docker section as a requirement, not as an alternative, if this patch can't be installed on the host. I would suggest changing:

It is possible to use this patch with nvidia-docker containers, even if host machine hasn't patched drivers. See Dockerfile for example.

to

If you are unable to install this patch on a host machine, it is possible to use this patch within nvidia-docker containers. See Dockerfile for example.