Arbiter.Arbiter

use Psr\Container\ContainerInterface in ActionHandler
rename ActionHandler::handle to avoid psr15 confusion
use psr15-like signature on ActionHandler

Radar.Action

Basically adds psr7 + 15 to Arbiter.
Uses Aura\Payload_Interface\ReadablePayloadInterface
requires psr7 + 15, arbiter, and aura/payload-interface

Radar.Adr

wires up all the components including relay, et al.

Radar.Router

Integrates Aura/Router with Radar/Actoin