Add clusterio module with API for lua code

Add a shared API for lua code through a module named clusterio.

modules/clusterio/impl.lua

@@ -0,0 +1,52 @@
+local api = require('modules/clusterio/api')
+
+
+local impl = {}
+
+local function init()
+    if not global.clusterio then
+        global.clusterio = {
+            instance_id = nil,
+            instance_name = nil,
+        }
+    end
+end
+
+-- Internal API
+clusterio_private = {}
+function clusterio_private.update_instance(new_id, new_name)
+    init()
+    global.clusterio.instance_id = new_id
+    global.clusterio.instance_name = new_name
+    script.raise_event(api.events.on_instance_updated, {
+        instance_id = new_id,
+        instance_name = new_name,
+    })
+end
+
+
+function impl.add_remote_interface()
+    remote.add_interface('clusterio_api', {
+        -- Returns a table of events raised by clusterio
+        get_events = function()
+            return api.events
+        end,
+
+        -- Returns the instance id the game is run under
+        -- This may change over time and/or be nil.
+        get_instance_id = function()
+            init()
+            return global.clusterio.instance_id
+        end,
+
+        -- Returns the name of the instance the game runs under.
+        -- This may change over time and/or be nil.
+        get_instance_name = function()
+            init()
+            return global.clusterio.instance_name
+        end,
+    })
+end
+
+
+return impl