Reintroduce "Jolla: Add preferredFeauters to example template" - non-Mer part

This reintroduces the non-Mer part of commit
af0ca3f9147312790ed27efd00d7c010edd09df3, temporarily reverted prior to
mer-3.1 merge with commit cea095600a2701d2e7d51b3d7d3a7c4612baf90a.

Signed-off-by: Martin Kampas <martin.kampas@jolla.com>
Reintroduce "Jolla: Add preferredFeauters to example template" - Mer part

This reintroduces the Mer specific part of commit
af0ca3f9147312790ed27efd00d7c010edd09df3, temporarily reverted prior to mer-3.1
merge with commit cea095600a2701d2e7d51b3d7d3a7c4612baf90a.

Signed-off-by: Martin Kampas <martin.kampas@jolla.com>
Reintroduce "Jolla: Add preferredFeatures support for welcomepage"

This reintroduces commit e3649e2a7ccaac1982d7f35ed5a55e926ea84f0f,
temporarily reverted prior to mer-3.1 merge with commit
cea095600a2701d2e7d51b3d7d3a7c4612baf90a.

Notice how it deals with 28e5eea (Example launcher: Don't configure kits
automatically) and 921f86d (TargetSetupPage: Generalize the page)

Signed-off-by: Martin Kampas <martin.kampas@jolla.com>
Reintroduce "Jolla: Add platform and preferedFeatures for tutorial parser"

This reintroduces commit a5e6696d0c5a786a72300a8ea83fc28d5def36b3,
temporarily reverted prior to mer-3.1 merge with commit
cea095600a2701d2e7d51b3d7d3a7c4612baf90a.

Signed-off-by: Martin Kampas <martin.kampas@jolla.com>