Update CMake to 3.9 (#70)

Co-authored-by: Michael Graeb <[email protected]>

Update MacOS to arm64 (#68)

BUILDER_VERSION: v0.9.55 (#66)

Fix warnings in public headers (#60)

Fix C++ One Definition Rules (ODR) Violations (#58)

**Issue:**
aws/aws-sdk-cpp#2137

**Description of Changes:**
Rename `decoder_state` -> `huffman_decoder_state` to avoid collision with same-named struct in aws-c-http.

fallback for target load (#55)

Refactor huffman testing file layout to fix nodejs runtime builds (#50)

* Let's try moving the header file to private

fix build warnings (#48)

Moved .inl test symbols into source file, fixes downstream swift build (

#46)

* Moved .inl test symbols into source file, fixes downstream swift build

* Fixed use of testing API

* Fixed shared-lib build

aws-fopen (#45)