Remove app-root-path

Resolve the relative path using path.relative instead of some hacky
string substitutions.

lib/factorioServer/index.js

@@ -15,7 +15,6 @@ const child_process = require("child_process");
 const path = require("path");
 
 const mkdirp = require("mkdirp");
-const appRootPath = require("app-root-path");
 
 const fileOps = require("lib/fileOps");
 

lib/factorioServer/index.spec.js

@@ -2,7 +2,6 @@ const assert = require("assert");
 const fs = require("fs");
 const path = require("path");
 
-const appRootPath = require("app-root-path");
 const parallel = require("mocha.parallel");
 const mkdirp = require("mkdirp");
 
@@ -75,7 +74,7 @@ describe("class factorioServer/index.js", ()=>{
 	describe(".createMap(mapName.zip)", ()=>{
 		it("creates a map file as instanceDirectory/saves/map.zip", async function(){
 			this.timeout(20000); // these test often takes a lot of time in the map creation step (4500 ms on i3 dev system)
-			let relativePath = __dirname.replace(appRootPath, "").substr(1);
+			let relativePath = path.relative('.', __dirname);
 			let server = new factorioServer({
 				instanceDirectory: path.join(relativePath, "_testData_createMap"),
 				instanceName: "Unit testing instance",
@@ -93,7 +92,7 @@ describe("class factorioServer/index.js", ()=>{
 		});
 		it("supports custom filenames", async function(){
 			this.timeout(20000);
-			let relativePath = __dirname.replace(appRootPath, "").substr(1);
+			let relativePath = path.relative('.', __dirname);
 			let server = new factorioServer({
 				instanceDirectory: path.join(relativePath, "_testData_createMap_2"),
 				instanceName: "Unit testing instance",

package.json

@@ -17,7 +17,6 @@
   "author": "Danielv123",
   "license": "ISC",
   "dependencies": {
-    "app-root-path": "^2.0.1",
     "as-table": "^1.0.31",
     "averaged-timeseries": "^1.4.0",
     "base64url": "^3.0.0",