Clean up the `build-info` and `results` files

The go version listings seem to have a `build-info` and `results` files
- if these are used, their purpose should be well documented, the example listing in the README should be updated.
- if they are not used, let's make sure to remove them.
- I do like the build-info file, it's useful to audit. is there more information that should go here? or can we make it better machine readable? (make it json or yml)
- the git hash should probably (also) go into the `dist.json`