|ach_name||The name of the achievement to clear (string).|
With this function you can tell the Steam API to clear (reset) a
specific achievement. The achievement should have been previously
defined on the Steamworks control panel accounts page for your game
and the string that is passed to the function should match that
used as the API Name on the control panel.
The above code will reset the achievements of the game when the user clicks the left mouse button.