0.4.0 (July 16)

• [BUGFIX] EventLoop::register requests all events, not just readable.
• [BUGFIX] Attempting to send a message to a shutdown event loop fails correctly.
• [FEATURE] Expose TCP shutdown
• [IMPROVEMENT] Coalesce readable & writable into ready event (#184)
• [IMPROVEMENT] Rename TryRead & TryWrite function names to avoid conflict with std.
• [IMPROVEMENT] Provide TCP and UDP types in mio (path to windows #155)
• [IMPROVEMENT] Use clock_ticks crate instead of time (path to windows #155)
• [IMPROVEMENT] Move unix specific features into mio::unix module
• [IMPROVEMENT] TcpListener sets SO_REUSEADDR by default