* Enable support for this in all ProjectConfiguration items
(Targets, projects, BCs, DCs, RCs, etc.). This is nicer
than having custom code in individual configuraiton items.
Reviewed-by: dt
* Add a DeployConfiguration class to hold settings related
to deployment.
* Add BuildStepsList to hold a list of buildsteps
* Update BuildConfiguration to use BuildStepLists instead of
manageing lists of buildsteps itself.
* Update BuildManager to use BuildStepLists in its interfaces
* Fix fallout introduced by API changes
* Update .user file to new way of storing settings
Task-number: QTCREATORBUG-1427
Task-number: QTCREATORBUG-1428
Task-number: QTCREATORBUG-1811
Task-number: QTCREATORBUG-1930
