Correctly handle track_file for keepalived < 2.1.0

[normelton]

Pull Request (PR) description

This PR solves two issues related to keepalive configuration:

• For versions of keepalived < 2.1.0, the "track_file" config stanza should be called "vrrp_track_file". The manpage for keepalived.conf confirms the deprecation, I found the exact version by digging through the source code for keepalived.
• The previous implementation of this module allowed a particular file to have a given weight, but when the track_file was referenced inside the vrrp_instance, the weight was reassigned to "1". According to the keepalived.conf manpage, the weight defined inside vrrp_instance defaults to weight configured in track_file. It should be safe to remove.

This Pull Request (PR) fixes the following issues

Fixes #278

[normelton]

Womp wimp, will fix those formatting errors sorry

[normelton]

Will resubmit a single commit without CI/CD errors