get coz profiler working

[tangentstorm]

https://github.com/plasma-umass/coz

https://blog.acolyer.org/2015/10/14/coz-finding-code-that-counts-with-causal-profling/

It ought to be usable with rust. Just need to figure out the rust equivalent of the C++ annotation macros.

[tangentstorm]

someone else got it working on rust: https://github.com/plasma-umass/coz/tree/master/rust