Apply tslint suggestions, round one

editors/code/src/config.ts

@@ -0,0 +1,23 @@
+import * as vscode from 'vscode';
+
+import { Server } from './server';
+
+export class Config {
+    public highlightingOn = true;
+
+    constructor() {
+        vscode.workspace.onDidChangeConfiguration((_) => this.userConfigChanged());
+        this.userConfigChanged();
+    }
+
+    public userConfigChanged() {
+        const config = vscode.workspace.getConfiguration('ra-lsp');
+        if (config.has('highlightingOn')) {
+            this.highlightingOn = config.get('highlightingOn') as boolean;
+        }
+
+        if (!this.highlightingOn && Server) {
+            Server.highlighter.removeHighlights();
+        }
+    }
+}