Update project layout for Swift Package Manager

[fulldecent]

Update the template layout so that libraries started with pod-template can be used from Swift Package Manager.

I recommend we take the AlamoFire approach: make it work but don't officially support it until SPM gets a stable API.

Here is a simple iOS framework which supports CocoaPods, Carthage, SPM, testing, an example project and CI https://github.com/fulldecent/FDChessboardView It is based entirely off the project layout for AlamoFire.

Please let me know if a PR that updates pod-template to be like that project would be well received.

---

Note on testing SPM compliance

Currently we cannot test SPM because it does not actually support iOS (https://stackoverflow.com/questions/34778823/swift-package-manager-uikit-dependency).

When SPM supports iOS we can use this Travis CI script:

sudo: required
before_install:
  - wget https://swift.org/builds/development/xcode/swift-DEVELOPMENT-SNAPSHOT-2016-03-01-a/swift-DEVELOPMENT-SNAPSHOT-2016-03-01-a-osx.pkg
  - export PATH=${PWD}/swift-DEVELOPMENT-*/usr/bin:"${PATH}"
  - installer -pkg swift-DEVELOPMENT-SNAPSHOT-2016-03-01-a-osx.pkg -target /
  - export PATH=/Library/Developer/Toolchains/swift-DEVELOPMENT-SNAPSHOT-2016-03-01-a.xctoolchain/usr/bin:"${PATH}"
script:
  - git clone https://github.com/apple/swift-package-manager
  - cd swift-package-manager && git checkout 151a973 && cd ../
  - swift-package-manager/Utilities/bootstrap
  - ${PWD}/swift-package-manager/.build/debug/swift-build
  - ${PWD}/swift-package-manager/.build/debug/swift-test

(adapted from http://ankit.im/swift/2016/02/17/swift-package-manager-testing-preview/)

OPEN PR: #179

[orta]

Depending on how wide a scope you want to make this, it could also cover trying to test these out on CI

[fulldecent]

I am thinking minimally viable product here is to make it work. Testing comes later (famous last words). I have just reached out to the Swift mailing list requesting assistance with this.

[orta]

👍

[fulldecent]

Update: clarified that this issue results in changing the layout of the project.

[orta]

Cool, yeah the layout makes sense - a warning this will be quite a bit of work simply making sure everything hooks back up again 👍

[fulldecent]

Update: this is fixed in #179.