Compose vessels from definitions and capabilities

InterceptorSpeedUpgrade.tres

@@ -0,0 +1,11 @@
+[gd_resource type="Resource" script_class="VesselUpgradeDefinition" load_steps=2 format=3]
+[ext_resource type="Script" path="res://VesselUpgradeDefinition.gd" id="1"]
+[resource]
+script = ExtResource("1")
+upgrade_id = "int_speed"
+display_name = "Thrusters"
+description = "+40 top speed, +60 acceleration per level."
+base_cost = 25
+max_level = 3
+icon = 18
+additive_modifiers = {"max_speed": 40.0, "acceleration": 60.0}