small refactoring

[phoenix344]

Okay I made some updates, because I was working with this module recently. This is a small refactoring that contains the following points:

• new Buffer(...) changed to Buffer.alloc(...) or Buffer.from(...)
• no hardcoded node_modules/
• ipv6 dependency has audit vulnerabilities and is outdated. The owner of the module suggested to replace it with the module ip-address
• added typescript declaration file

Tests seems like to work as intended.
hope this project isn't as dead as it looks like.