Update README.md

Author: kyle-wannacott

README.md

@@ -63,7 +63,7 @@ Examples on using table-sort-js with frontend frameworks such as [React.js](http
 
 | <th> classes | Description                                                                                                                              |
 | ------------------ | ---------------------------------------------------------------------------------------------------------------------------------------- |
-| "data-sort"        | Sort by [data attributes](https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes), e.g <td data-sort="42">  |
+| "data-sort"        | Sort by [data attributes](https://developer.mozilla.org/en-US/docs/Learn/HTML/Howto/Use_data_attributes), e.g <td data-sort="42">. Useful for doing custom sorts.  |
 | "dates-mdy-sort"   | Sorts dates in US style mm/dd/yyyy format;. e.g (12/28/2023). Can use "/" or "-" as separator. Overides inferred "dates-dmy-sort" class. |
 | "onload-sort"      | Sort column on loading of the page. Simulates a click from the user. (can only sort onload for one column)                               |
 | "disable-sort"     | Disallow sorting the table by this specific column.                                                                                      |