Adding prebuilt binaries avoids requiring Rust tooling everywhere.

In the attempt to solve this I played around with napi-rs (see rafaelmaeuer/node-crc/tree/dev/napi) unless I found out, that cargo already produces the prebuild-binary: index.node.

After learning about the necessity of cross-platform binaries (invalid ELF header in Github actions) I ended up writing a build-script based on cross-rs and rustup/cross-compilation which can produce binaries for following platforms (inspired by sharp):

• macOS x64
• macOS ARM64
• Linux x64 (gnu/musl)
• Linux x86 (gnu/musl)
• Linux ARM64 (gnu/musl)
• Windows x64
• Windows x86

I slightly modified the lib to load the correct binary on each platform and Mocca-Tests are still passing:

  CRC-8 Family
    ✔ should calculate CRC-8(CRC-8-ATM)
    ✔ should calculate CRC-8-CDMA

  CRC-16 Family
    ✔ should calculate CRC-16(CRC-16-IBM)
    ✔ should calculate CRC-16-CCITT(CRC-CCITT)

  CRC-24 Family
    ✔ should calculate CRC-24
    ✔ should calculate CRC-24 (using poly)

  CRC-32 Family
    ✔ should calculate CRC-32(CRC-32-IEEE) which is also called crc32b in mhash library
    ✔ should calculate crc32 according to the mhash library
    ✔ should calculate CRC-32-C

  CRC-64 Family
    ✔ should calculate CRC-64(CRC-64-ECMA)
    ✔ should calculate CRC-64-ISO
    ✔ should calculate CRC-64-WE
    ✔ should calculate CRC-64-JONES


  13 passing (9ms)

I also created a changelog file from the git history, therefore this PR closes #7, closes #8 and closes #9.

A next step would be to let github-actions produce the binaries and download them from github-artifacts on install.