Add showWorkspaceLoadedNotification to vscode client

This allows users to control whether or not they want to see the "workspace
loaded" notification.

This is done on the server side using InitializationOptions which are provided
by the client. By default show_workspace_loaded is true, meaning the
notification is sent.

editors/code/src/config.ts

@@ -8,6 +8,7 @@ export class Config {
     public highlightingOn = true;
     public enableEnhancedTyping = true;
     public raLspServerPath = RA_LSP_DEBUG || 'ra_lsp_server';
+    public showWorkspaceLoadedNotification = true;
 
     private prevEnhancedTyping: null | boolean = null;
 
@@ -24,6 +25,12 @@ export class Config {
             this.highlightingOn = config.get('highlightingOn') as boolean;
         }
 
+        if (config.has('showWorkspaceLoadedNotification')) {
+            this.showWorkspaceLoadedNotification = config.get(
+                'showWorkspaceLoadedNotification'
+            ) as boolean;
+        }
+
         if (!this.highlightingOn && Server) {
             Server.highlighter.removeHighlights();
         }