Desktop: Simplified and improve command service, and added command palette

- Commands "enabled" state is now expressed using a "when-clause" like in VSCode
- A command palette has been added to the Tools menu

ReactNativeClient/lib/services/commands/commandsToMarkdownTable.ts

@@ -0,0 +1,32 @@
+import markdownUtils, { MarkdownTableHeader, MarkdownTableRow } from 'lib/markdownUtils';
+
+export default function commandsToMarkdownTable():string {
+	const headers:MarkdownTableHeader[] = [
+		{
+			name: 'commandName',
+			label: 'Name',
+		},
+		{
+			name: 'description',
+			label: 'Description',
+		},
+		{
+			name: 'props',
+			label: 'Props',
+		},
+	];
+
+	const rows:MarkdownTableRow[] = [];
+
+	for (const commandName in this.commands_) {
+
+		const row:MarkdownTableRow = {
+			commandName: commandName,
+			description: this.label(commandName),
+		};
+
+		rows.push(row);
+	}
+
+	return markdownUtils.createMarkdownTable(headers, rows);
+}