Update README.md re conversion of AboutBox docs

Added AboutBox project to table of completed documentation (in correct
format for lib-docs site).

Author: delphidabbler

README.md

@@ -16,6 +16,7 @@ Documentation of the following projects has been completed:
 
 | Project | Starting page URL |
 |---------|-------------------|
+| About Box Component | <https://lib-docs.delphidabbler.com/AboutBox/> |
 | Clipboard Viewer Component | <https://lib-docs.delphidabbler.com/CBView/> |
 | Drop Files Components | <https://lib-docs.delphidabbler.com/DropFiles/> |
 | Environment Variables Unit | <https://lib-docs.delphidabbler.com/EnvVars/> |