Added swift_version to PromisesSwift.podspec. Fixing issue #150 where cocoapods require `swift_version` to be specified if Podfile declares `:inherit_targets => false`.
Added swift_version to PromisesSwift.podspec.
Fixing issue #150 where cocoapods require `swift_version` to be specified if Podfile declares `:inherit_targets => false`.

google/promises,google/promises