Add Swift Package Manager support

• [Feature] Add Swift Package Manager (SPM) support
• [Pod] Bump minimum iOS version to 9.0

Support for tvOS and watchOS

2.1.1

Eliminate new pod lint warnings (#34)

Fix Xcode 8.3 Warnings

Merge pull request #29 from yahoo/prep/2.0.1

Prep 2.0.1 release

Improved support for Objective-C++

• Changed newer @include statements to old-style #import to support an Obj-C++ project.
• Clarified some comments
• Reduce OS X minimum version to 10.8

Encryption Support

Expose NSDataWritingOptions to clients (adds support for encryption on iOS)

Fix iOS 7 crash upon removing a nil value from the cache

1.2.2

Prepare for 1.2.2

Fix bug: unable to remove a single value from the cache

Using Objective-C literal syntax for removing a single value from an NSMutableDictionary isn't actually documented and doesn't work in all versions of iOS.

Delegate callbacks around auto-save

• [Feature] Delegate callbacks for auto-save pre/post/fail
• [Refactor] Reduce log messages and fix log message format
• [Travis] Log expiration of code signing certificate on build

Minor dependency fix

[fix] Unpinned Specta from commit back to a tagged version

Better cache change notifications

[Feature] Added support for tracking item removal through a new change notification. Deprecated existing notification.
[Refactor] XCode 7 support