move the versions manager to its own module

lib/core/engine.js

@@ -296,11 +296,7 @@ class Engine {
   }
 
   libraryManagerService(_options) {
-    const LibraryManager = require('../versions/library_manager.js');
-    this.libraryManager = new LibraryManager({
-      plugins: this.plugins,
-      config: this.config
-    });
+    this.registerModule('library_manager');
   }
 
 }

lib/modules/library_manager/index.js

@@ -2,14 +2,11 @@ var Npm = require('./npm.js');
 
 class LibraryManager {
 
-  constructor(options) {
-    this.plugins = options.plugins;
-    this.config = options.config;
+  constructor(embark) {
+    this.config = embark.config;
     this.contractsConfig = this.config.contractsConfig;
     this.storageConfig = this.config.storageConfig;
 
-    this.embark = this.plugins.createPlugin('libraryManager', {});
-
     this.determineVersions();
 
     this.registerCommands();

lib/modules/library_manager/npmTimer.js

@@ -1,11 +1,9 @@
 const {PerformanceObserver, performance} = require('perf_hooks');
 require('colors');
 const utils = require('../utils/utils.js');
-// TODO: remove this
-const i18n = require('../core/i18n/i18n.js');
+const i18n = require('../../core/i18n/i18n.js');
 i18n.setOrDetectLocale('en');
 
-
 class NpmTimer{
   constructor(options){
     this._logger = (options.logger && typeof options.logger.info == 'function') ? options.logger : console;