GenericProject: Use some Qt 5 connect

Change-Id: I990aa7a6f59fa323d2d8e3c90bf89b18f6fc2058
Reviewed-by: hjk <hjk121@nokiamail.com>
Help: Save side bar visibility without keeping track manually

Change-Id: I95982455a996cdec3a68f3db5cf714a609207814
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>