Status.md: Update the implementation status of various types
Status.md: Update the implementation status of various types

- Also misc formatting tidyups.

parkera/swift-corelibs-foundation,apple/swift-corelibs-foundation,e78l/swift-corelibs-foundation,e78l/swift-corelibs-foundation,apple/swift-corelibs-foundation,parkera/swift-corelibs-foundation,apple/swift-corelibs-foundation,parkera/swift-corelibs-foundation,e78l/swift-corelibs-foundation,e78l/swift-corelibs-foundation,parkera/swift-corelibs-foundation,e78l/swift-corelibs-foundation,parkera/swift-corelibs-foundation,apple/swift-corelibs-foundation,apple/swift-corelibs-foundation