Missing accessiblity attributes in UI components

[jreznot]

Environment

• Platform version: 6.9.0

• Client type: Web

Description of the bug or enhancement

Missing accessibility attributes:

1. Page - title attribute
2. Menubar
   role of menuItem on all items
   aria-label on all menu items
3. Filter
   aria-labelledby attribute to link maxResultsLabel to maxResults fields (textfield and button)
   aria-label on filtersPopupButton
   aria-label on settingsBtn
4. Table headers
5. DataGrid
   summary attribute on table
   scope attribute on all header cells
   aria-label on context menu
6. Tab Panel
   aria-labelledby to current tab’s label ID
7. Date Fields
   aria-labelledby to link text input to field’s label

Relates to #641