Move bitrotted programs for iOS, Playbook and Qt to attic/
Merge pull request #583 from kossebau/moveBitrottedAppsToAttic

Move bitrotted programs for iOS, Playbook and Qt to attic/
Add target webodf.js.zip-target
Rename product targets and add consistent prefix "-product"
Note the products which can be built currently in README-Building.md
Add note to remove build target "zip" when CI no longer uses it