updates to deps, testing, ci, msvs handling

[ducktrshessami]

• Updates dependencies
• Updates test handling
  • Replaced deprecated mocha-istanbul with nyc
  • Updates test 245 crypto_stream verify parameters bad param 1 number for newer Node.js versions Still uses old behavior for older Node versions since some are still under maintenance LTS
• Replaces old Travis CI config and badge with GitHub workflow and badge
• Newer versions of Visual Studio use latest MSVC toolset build of libsodium binaries (see C++ binary compatibility between Visual Studio versions)

The replacement of Travis had more to do with the original config failing on the new Travis site and GitHub workflows being free than any other reasons. The only thing I find the workflow CI being unable to test is older Visual Studio versions.

[ducktrshessami]

bumperino