Add independent Rust engine, deterministic mod API and asset pipeline

examples/mods/aurora/mod.toml

@@ -0,0 +1,7 @@
+id = "aurora"
+name = "Aurora Field Trials"
+version = "1.0.0"
+api_version = 1
+description = "A short mission with a scripted pulse cannon, weaving drones and repair cells. Uses your installed original artwork."
+content = "content.json"
+scripts = ["scripts/weapon.rhai", "scripts/drone.rhai", "scripts/cell.rhai", "scripts/mission.rhai"]