Wasm89 - Wasm for bad compilers

This is a port of wac-esp with the following changes to support bad/outdated c89/c90 compilers, for when you have to deal with outdated vendor toolchains.

Changes:

• Removed dependency on stdint.h
• Doesn't need snprintf
• Comments style changed from // to /*
• Removed ESP specific code
• Replaced clz/popcnt/etc builtins with slow c versions
• Replaced c89 missing float ops
• Moved inline variable definitions to start of function
• Added extern "C" guards for use from c++
• Added support for "Sign Extention Extension"
• Add test environment
• Passes a large amount of WG-1.0

Compiler requirements:

This currently requires the following non-standard features, pull requests to change this are welcome:

• A 64 bit integer type long long / _int64
• Parser support for variadic macros (or remove all the logs)

Compiler support:

• clang
• gcc
• MSVC 2008 or newer (Tested with 15.0.21022.08)

Architecture support:

• ARMv4T
• ARM64
• x86
• x86_64