Support for the new `watchos` platform

Skipped by `examples:build` for now, because it breaks with Xcode < 7.0

This reverts commit 782576c4bf19421534de0b34bba1895ee6df711b.

Closes https://github.com/CocoaPods/CocoaPods/issues/3689.

[Command] Ensure warnings are printed even when theres an exception

Deduplicate pod targets

Remove the "Pods-" prefix from the labels in the expected error messages, because the fixture targets are deduplicated.

For disambugiation with stdlib's debugging helper #inspect.

Instead of refering to the global configuration

One scoped target for each target definition