0.5.1

• Added json_mapping macro.
• Added Signal module.
• Added Tempfile class.
• Enhanced HTTP::Client.
• Added OAuth::Consumer.
• Added OAuth2::Client.
• Added OpenSSL::HMAC.
• Added SecureRandom.
• New syntax for array/hash-like classes. For example: Set {1, 2, 3} and HTTP::Headers {"content-type": "text/plain"}. These just create the type and use << or []=.
• Optimized Json parsing performance.
• Added a CSV builder.
• XML reader can parse from an IO.
• Added Dir::glob and Dir::Entries (thanks @jhass)
• Allow ensure as an expression suffix.
• Fixed #219: Proc type is not inferred when passing to library fun and the return type doesn't match.
• Fixed #224: Class#new doesn't pass a block.
• Fixed #225: ICE when comparing void to something.
• Fixed #227: Nested captured block looses scope and crashes compiler.
• Fixed #228: Macro expansion doesn't retain symbol escaping as needed.
• Fixed #229: Can't change block context if defined within module context.
• Fixed #230: Type interference breaks equality operator.
• Fixed #233: Incorrect no block given message with new.
• Other bug fixes.