change layout styles, move BoardPage to separate file

src/View/ChatPages/boardPage.tsx

@@ -0,0 +1,10 @@
+import * as React from "bloatless-react";
+
+import BoardViewModel from "../../ViewModel/Pages/boardViewModel";
+
+export function BoardPage(boardViewModel: BoardViewModel) {
+  return <div class="pane">
+    <div class="toolbar"></div>
+    <div class="content"></div>
+  </div>;
+}