URL is a variable set in branding.desc, distros cna link to a Known Issues page
text for the URL is also possible to set in branding, known issues is default
advantage is any text possible as distros see fit
disadvantage, not part of translated strings
if most agree, Known Issues can be set as hard coded text, not in branding.desc
Renamed ViewPlugin to ViewStep.
Back/Next button status management.
Subpages are now under a ViewStep's jurisdiction, we only forward back/
next signals if a ViewStep says it's got more pages to show. ViewStep
exposes a QWidget* to ViewManager, this QWidget gets added to a stack.
If a ViewStep wishes to show more than one page, it must manage more
pages on its own inside its single QWidget*.
