Version 0.2.0

Added

• Add swift package manager support.

Changed

• Improve JSON reader performance for gcc.
• Improve double number reader performance with a fast path.
• Rewrite double number writer with Schubfach algrithm: #4.
• Strict UTF-8 validation for JSON reader.

Removed

• Remove YYJSON_READ_FASTFP flag.

Fixed

• Fix a compile error for old version gcc on linux: #7.