(core) Add info and hover tooltips

Summary:
Adds tooltip buttons to various parts of the UI that either open a popup with
information when clicked, or show a label on hover.

Test Plan: Project tests.

Reviewers: jarek

Reviewed By: jarek

Differential Revision: https://phab.getgrist.com/D3657

app/client/ui/Tools.ts

@@ -198,7 +198,13 @@ function addRevertViewAsUI() {
         ),
         tooltipCloseButton(ctl),
       ),
-      {openOnClick: true}
+      {
+        openOnClick: true,
+        closeOnClick: false,
+        openDelay: 100,
+        closeDelay: 400,
+        placement: 'top',
+      }
     ),
   ];
 }