Listen to Plugin.Unloading.

Closes #127.

plugin/src/init.server.lua

@@ -4,10 +4,6 @@ end
 
 local Roact = require(script.Parent.Roact)
 
-Roact.setGlobalConfig({
-	elementTracing = true,
-})
-
 local App = require(script.Components.App)
 
 local app = Roact.createElement(App, {
@@ -16,4 +12,6 @@ local app = Roact.createElement(App, {
 
 Roact.mount(app, game:GetService("CoreGui"), "Rojo UI")
 
--- TODO: Detect another instance of Rojo coming online and shut down this one.
+plugin.Unloading:Connect(function()
+	Roact.unmount(app)
+end)