meta: setup continuous benchmarking

[ankush]

1. Get a new bare metal server
2. Run benchmarks nightly
3. Upload data somewhere
4. Ensure concurrency of 1 somehow (?) = Never run multiple things at the same time on the benchmarking server.
5. Dashboards, pretty charts
6. Alerts

[epompeii]

@ankush you may want to check out Bencher: https://github.com/bencherdev/bencher

Bencher supports 2, 3, 5, & 6 out of the box, for free for public projects. Points 1 & 4 are also available. I'm the maintainer of Bencher, so I would be more than happy to help answer any questions.