v2.2.0

• Update Travis Node versions; Node < 10 no longer maintained 571bcdf
• Update dependencies and prep for v2.2.0 release 19f6700
• Add option for stable stringifying to JSON (#90) (#91) ec7d624
• Add replacer for bigint on json formatter (#84) 432d7a8
• Fix timestamp format type definitions to accept a function (#79) 4c4d1e3

2.1.2...v2.2.0