* Migrate LinterCache to use Codable models
improving performance and type safety
* Fix Linux
* Avoid creating a Decoder if it won't be used
For example if the file doesn't exist or can't be read.
* Use corelibs plist coder if available
It's available in the Swift 5.1 branch: https://github.com/apple/swift-corelibs-foundation/pull/1849
* Remove unused error case
The MIT license doesn't require that all files be prepended with this
licensing or copyright information. Realm confirmed that they're ok with this
change. This will enable some companies to contribute to SwiftLint and the
date & authorship information will remain accessible via git source control.
JP Simard