Setter Generals are not displayed as piston by default

[larspalo]

A general defined in ODF will display as piston by default, but currently a setter GeneralXX won't. The setter generals are displayed correctly as pistons on the generals panel, but not if I add them to a panel myself. By default the setter generals are now displayed as drawstops. I attach an .organ file that display the issue.

GeneralBug.zip

Also, I think we need to update the help that simply states that certain elements are displayed as button by default but the correct wording should be either displayed as piston or drawstop - which would match the apparent display in GO.