[Xcodeproj] Adapt for Project initialization changes
[Xcodeproj] Rename Project::save_as
[Xcodeproj] Adapt for improved path handling
[Xcodeproj][Project] Remove build configurations from initialization
[Project] Cleanup
[Project] Overhaul
[Project] Rename Local Pods group do Development Pods
[Project] Store Pods support files inside their group
[Installer] Sort Pods project recursively
[Project] Group subspecs in a group to avoid name collisions with other groups

Otherwise a subspec named resources would be added to the resources
group already used to store the resources of the main spec
[Project] Store Pods products inside their group
[Installer] Add system frameworks directly and add them to the targets

Systems frameworks are present only for illustrative purposes and adding
them in the target installers of the pods prevents incremental editing
of the Pod project