4.4.0

• Adds tagged pointers to the CAtomics package, taking advantage of 128-bit atomic instructions in x64 and ARM64
• Adds cache-aligned variants to various types from CAtomics. These types take an entire cache line to themselves, which can be useful in some cases.
• Adds initializers, such as AtomicInt32.init(_ value: Int32) and AtomicRawPointer.init(_ pointer: UnsafeRawPointer). Previously one had to use a default initializer followed by a call to the initialize method.
• Adds a compare-and-swap operation to AtomicReference
• Supports the Windows build of Swift