Add metadata to results

[egpbos]

Is it possible to add more metadata to the benchmarks?

I'm using ASV for a C++ project, so I'm thinking in particular of compiler version. This is not specified as a dependency, so I would just like to pick it up from the command line.

Also, I'm wondering if it's possible to add the versions of the Conda packages that I do use as dependencies, but that I don't pin specifically, i.e. I'm just using empty strings to download latest versions, but would still like to record which versions I'm using.

[kevingerman]

Its a hack, but in the current head (v0.5*) I have been assigning environment variables in the asv.conf.json and then grabbing those as params for the tests. In my case it's features like cluster size or a dataset tag.

[mattip]

This would be helpful for NumPy as well. As we begin to use SIMD intrinsics it would be nice to be able to report the intrinsics actually used at runtime in the benchmarks json results.