Add meaningful label to colour items in colour chooser elements

Initial setup: Add fontcolor and backcolor to the Atto toolbar at: Dashboard > Site administration > Plugins > Text editors > Atto HTML editor > Atto toolbar settings Go to any page that has an Atto editor. Ex: Edit Profile page (Description field). A screen-reader (NVDA or ChromeVox) for this test Atto Font Color testing: Use your keyboard to navigate between the buttons of the Atto toolbar until you reach the Font Color button. Press Enter to open the Font Color chooser menu. Verify  you will see 6 colour items to choose from. Use your keyboard to navigate between the colour items. Verify  that you hear the words " [Colour name] " for each navigation. Ex: White. Atto Background Color testing: Use your keyboard to navigate between the buttons of the Atto toolbar until you reach the Background Color button. Press Enter to open the Background Color chooser menu. Verify  you will see 6 colour items to choose from. Use your keyboard to navigate between the colour items. Verify  that you hear the words " [Colour name] " for each navigation. Ex: White.