Cache — 6.0.0

Breaking changes

• Bumped minimum deployment target iOS 11.0, macOS 10.12 and tvOS 11

• Changed API so they key can be any Hashable not just string, in order to make the old code work we need to add String to our Storage declaration. (Added by @nerdsupremacist, thanks!)

// Old
Storage<Image>

// New
Storage<String, Image>