css: fix disabled buttons appearing clickable.

Fix buttons appearing to be clickable when in the disabled state.

Submit buttons are normally disabled after a form is submitted. Before
these buttons would still look clickable. Now disabled buttons are greyed
out instead of looking the same as normal buttons.

app/javascript/src/styles/base/010_reset.scss

@@ -34,7 +34,3 @@ ol, ul {
 a:focus {
   outline: thin dotted;
 }
-
-button, input[type="button"], input[type="submit"] {
-  cursor: pointer;
-}