* add CONTRIBUTING guidelines and initial changelogs

* Update CONTRIBUTING.md

Co-Authored-By: David <dvdplm@gmail.com>

* [CONTRIBUTING] address some of the review comments

* [CONTRIBUTING] mention our code style

* rustfmt (sorry not sorry)

* unscrew uint macros fmt

* rustfmt: max width 120

* rustfmt: use_small_heuristics = "Max"

* fix CI

* argh

* CONTRIBUTING: mention gitter

* impl-serde: bump to 0.2.3

* Revert "impl-serde: bump to 0.2.3"

This reverts commit 3fd73cbc6a61afedebd3118445dabbfaea778714.

* fmt

* impl-serde: update changelog for 0.2.3