Runtime is now configurable. Adds a tunable config for modifying the
size of pre-allocations for actor messaging channels, and for selecting
the number of threads the runtime will use.
Did not like the requirement of a tokio runtime and async/await. Rewrote
to use lock free queues (`crossbeam_queue::ArrayQueue`) as the basic
primitive to enable a runtime consisting of many pseudo-processes that
can pass messages to each other.
Co-authored-by: Zachery Aaron Shores-Chmielewski <zachanon@gmail.com>
Reviewed-on: http://zachery.lol/code/code/zacheryasc/swactor/pulls/1
