support jackson's fast number parsing/writing features

[pjfanning]

Jackson's JsonFactory supports these features.

• StreamReadFeature.USE_FAST_DOUBLE_PARSER
• StreamWriteFeature.USE_FAST_DOUBLE_WRITER
  When you create a Jackson ObjectMapper, you can optionally supply a JsonFactory.

Just thought I'd raise awareness of these features of jackson (v2.14.0 and above). With the StreamReadFeature and StreamWriteFeature, you would probably want to make those opt-in - that chesire should probably not use them by default.

[dakrone]

Thanks for letting me know about them. Looks like a few other things have changed around here too.