Closes CocoaPods/CocoaPods#1309

Fix "cannot overwrite directory" when copying OS X frameworks into the resources dir

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

Otherwise a subspec named resources would be added to the resources
group already used to store the resources of the main spec

* master:
  Update CHANGELOG for #1294
  [rake] Welcome to the real world, where envs don’t automagically work.
  [Installer] Add all the user's build configurations to the Pods project.
  [Analyzer] Resolve all user build configurations.
  Misc small changes.
  Rebuild integration specs.
  Update Xcodeproj to the latest master revision
  Use the build configurations from the Podfile for the Pods project
  Add test for STRIP_INSTALLED_PRODUCT = NO at project level
  Fix all callers of Pod::Project.new()
  Handle the build_configurations parameter in Xcodeproj::Project subclasses
  Pass the user build configurations to the Pods project

This patch also improves indentation.

/c @ianyh

/c @ianyh

Pass the user build configurations to the Pods project

Was missing a `bundle exec`.