Is your feature request related to a problem? Please describe.

I would like to simplify the build and deployment of RMM by making it a header-only library.

After #396 and #407, RMM has no components that need to be built into a shared object file.

Additional context

If like me you're wondering, "Does the default resource machinery with function local statics prevent RMM from being able to be header only?", then I already verified that yes, it works as intended. See: https://github.com/jrhemstad/link_test