Fix checkbox label description

[zepfietje]

Should be clickable to toggle checkbox.
Also make sure it's horizontally aligned with the label (not with the checkbox).

[danharrin]

Checkbox form components don't have a description and the label is clickable.

Checkbox list components have a description, and both the label and description is clickable. The description is horizontally in line with the label and not the checkbox.

[zepfietje]

The description, currently called helper text, should be horizontally aligned with the label, which is currently not the case.