Package errors provides simple error handling primitives.
Read more on https://github.com/pkg/errors

This reverts commit 1baef567.

this makes it unnecessary to cast it to int when calling the netlink API

This reverts commit a5bccc29, reversing
changes made to 88c1c813.

- Remove Makefile for adding it later in a seperate PR
- Remove main files which where added by accident
- Add constants for IPv4 and IPv6
- Improve log messages
- Simplify netlink_reader addPathsToClients and removePathsFromClients
- Refactor Route's Equal function
- Return false for ECMP in netlink_path since ecmp is currently not
implemented in netlink