Release 0.9.1

Release 0.9.0

Release 0.8.0

Release 0.7.1 (msgspec#132)

Release 0.7.0

Updates changelog. Also adds github PR links for all changelog entries.

Add "Why msgspec?" section to docs

Fixup decode(..., type=Struct) optimization

Between the original PR being made and merged a change went in that
broke the optimization (specifically, the type code for struct types was
split into `MS_TYPE_STRUCT` and `MS_TYPE_STRUCT_ARRAY`). This fixes the
bug, and expands the tests to provide a more localized check for this
behavior.

Add type annotation for `__struct_fields__`.

Document nogc

Fix sdist

Include `.h` files in sdist builds.