replace Observable.ts with @lume/eventful and remove lowclass

Author: trusktr

dist/Observable.d.ts

@@ -1,10 +1,15 @@
-import { Observable } from './Observable.js';
+declare const FileScanner_base: (new (...a: any[]) => {
+    on(eventName: string, callback: Function, context?: any): void;
+    off(eventName: string, callback?: Function | undefined, context?: any): void;
+    emit(eventName: string, data?: any): void;
+    "__#1@#eventMap": Map<string, [Function, any][]> | null;
+}) & (new (...a: any[]) => object);
 /**
  * @class FileScanner - Scans files for JSDoc-style comments, outputting usable
  * objects representing the found tags.
- * @extends Observable
+ * @extends Eventful
  */
-export declare class FileScanner extends Observable {
+export declare class FileScanner extends FileScanner_base {
     /**
      * @method scanFile - Scans a file and triggers the 'comment' for each comment
      * that the scanner parsers while scanning the file.

dist/Observable.d.ts.map

@@ -45,6 +45,7 @@
 	},
 	"homepage": "https://github.com/trusktr/readem",
 	"dependencies": {
+		"@lume/eventful": "^0.3.2",
 		"army-knife": "^0.2.0",
 		"async": "^0.9.0",
 		"at-at": "^1.1.0",
@@ -53,7 +54,6 @@
 		"ejs": "^2.2.4",
 		"highlight.js": "^8.4.0",
 		"jsdoctypeparser": "^6.1.0",
-		"lowclass": "^7.0.0",
 		"lume": "0.0.0-rc.0",
 		"mkdirp": "^0.5.1",
 		"rndm": "^1.1.0",