Added typescript package, updated eslint & defined tsconfig

.eslintrc.json

@@ -1,12 +1,22 @@
 {
 	"root": true,
 	"parserOptions": {
+		"parser": "@typescript-eslint/parser",
 		"ecmaVersion": 2020,
 		"sourceType": "module"
 	},
-	"extends": ["eslint-config-airbnb-base", "plugin:prettier/recommended"],
-	"plugins": ["mocha"],
+	"extends": [
+		"eslint-config-airbnb-base",
+		"plugin:@typescript-eslint/recommended",
+		"plugin:prettier/recommended"
+	],
+	"plugins": ["mocha", "@typescript-eslint"],
 	"rules": {
+		"lines-between-class-members": [
+			"error",
+			"always",
+			{ "exceptAfterSingleLine": true }
+		],
 		"max-classes-per-file": 1,
 		"no-empty": [
 			2,
@@ -16,7 +26,8 @@
 		],
 		"no-promise-executor-return": 1,
 		"no-shadow": "off",
-		"no-underscore-dangle": "off"
+		"no-underscore-dangle": "off",
+		"@typescript-eslint/no-var-requires": "off"
 	},
 	"env": {
 		"mocha": true