1.0.22

• Upgrade to ZeroMQ 4.2.0 stable (up from 4.1.6).
• Add context.setBlocky and context.setMaxMessageSize (new in 4.2)
• Various documentation updates to manual and SocketType.
• Prevent automatic deinitializer context and socket cleanup if already closed.
• Provide context.close() as an alias for terminate for consistency.
• Reorganize Xcode project structure and move libzmq platform-specific files
  to its own Libraries folder (was in Sources).
• Fix example project build issues (namely watchOS)