opack-0.2.1

What's Changed

• Add ryu string conversion by @devjeonghwan in #42
• Add fast double and long by @devjeonghwan in #43
• Change singleton style of Json to ThreadLocal by @devjeonghwan in #44
• Change list and map transformers to use generic types for deserialize by @devjeonghwan in #45

Full Changelog: 0.2.0...0.2.1