CHANGES (p.yaml.3.1.0.doc.CHANGES)

Support Yaml 1.2, and stop advertising Yaml 1.0 support. This also updates the vendored libyaml to 0.2.5 (@favonia #37).
Add a Yaml.Util module with a number of useful combinators to manipulate Yaml.value types, such as retrieving keys and values, finding entries and converting to OCaml native types (@patricoferris #43)
Move the sexpression derivers into a separate Yaml_sexp package (the yaml-sexp opam package). This reduces dependencies on the main library. You can still use Yaml types in ppx_sexplib_conv derivers by simply replacing the Yaml.value (or other type) with Yaml_sexp.value which is an alias that also includes the Sexp conversion functions in its scope. (@alan-j-hu @avsm #46).
When outputting values, wrap special values like "true" or "1.0" in double quotes, so that Yaml.of_string will not interpret them as a non-string value (@avsm #47).
Track anchors and mappings in Yaml.yaml (but not in the Yaml.value JSON representation). This also allows non-scalar values to be used as keys. (@favonia #38)
Bump the internal write buffer for stream emission to 256k from 64k, as people are writing ever-larger Yaml files! In the future, this static buffer will be replaced by a dynamically growing output buffer but for now needs to be set manually.
The minimum supported OCaml version is now OCaml 4.05.

Fix a memory unsoundness issue with larger files in the bindings to libyaml, which fixes spurious errors when parsing larger YAML files (#35 marcinkoziej)
Expose more information about error locations while parsing a Yaml file (#34 @marcinkoziej)
Add test for a large Yaml file (#30 @pmonson711)
Bump size of internal serialisation buffer in to_string to 64KB from 16KB (@avsm).
Switch CI to GitHub Actions (@avsm)
Depend on dune-configurator in the build to be compatible with dune 2.0 and higher (@avsm)

Add unexpected error codes to error messages so that debugging errors from libyaml is possible (#28 @mjambon)

Represent quoted scalars as strings in Json encoding (#22 @rizo, fixes #20).
Expose more detailed scalar information in Yaml.yaml (#22 @rizo).
Add Yaml.equal (#22 @rizo)
Avoid printing the decimal point when the float number is an integer (#25 @kit-ty-kate)

Support parsing of canonical Yaml null, float and bool values (@avsm, fixes #15 #16).
Port from jbuilder to dune (#2 @rgrinberg)
Use dune.configurator for config probing (#18 @emillon)
Upgrade opam metadata to 2.0 format (@avsm)
Suppress some C warnings on build due to ctypes autogen until ctypes gains support for unsigned char types (@avsm)
Add Windows build support (@avsm #11)
Refresh libyaml to upstream changeset 85d1f168ef39f4 (@avsm)
Switch CI to Azure Pipelines and test Windows, Linux and macOS (@avsm)
Add Junit output to the Alcotest (@avsm)

Repair build on ppc64le by using Configurator to query CFLAGS. ppc64le needs an mcmodel=small due to a quick of the architecture.
Minor improvements to ocamldoc documentation.
Remove pkg/pkg.ml as dune-release is used for release now.