Rename Slave to Host

The role of a slave as a host for Factorio servers is not well reflected
in its name and has caused confusion among users.  Rename slave to host
to better reflect its role as a host of Factorio servers.

plugins/inventory_sync/instance.js

@@ -41,7 +41,7 @@ class InstancePlugin extends libPlugin.BaseInstancePlugin {
 			this.disconnecting = false;
 			(async () => {
 				for (let player_name of this.playersToRelease) {
-					if (!this.slave.connector.connected || this.disconnecting) {
+					if (!this.host.connector.connected || this.disconnecting) {
 						return;
 					}
 					this.playersToRelease.delete(player);
@@ -63,7 +63,7 @@ class InstancePlugin extends libPlugin.BaseInstancePlugin {
 			message: "Controller is temporarily unavailable",
 		};
 
-		if (this.slave.connector.connected && !this.disconnecting) {
+		if (this.host.connector.connected && !this.disconnecting) {
 			try {
 				response = {
 					player_name: request.player_name,
@@ -85,7 +85,7 @@ class InstancePlugin extends libPlugin.BaseInstancePlugin {
 	}
 
 	async handleRelease(request) {
-		if (!this.slave.connector.connected) {
+		if (!this.host.connector.connected) {
 			this.playersToRelease.set(request.player_name);
 		}
 
@@ -104,7 +104,7 @@ class InstancePlugin extends libPlugin.BaseInstancePlugin {
 	}
 
 	async handleUpload(player_data) {
-		if (!this.slave.connector.connected || this.disconnecting) {
+		if (!this.host.connector.connected || this.disconnecting) {
 			return;
 		}