Update CiviHR code to be CiviCRM 5.16 complient and convert CiviHR ca…

[seamuslee001]

…che group to be standard Civi::cache style

Overview

This removes some uncessary caching storing as it doesn't appear to be doing. This also adds in a new cache.civihr service which is in the standard format as Civi::cache. Also it updates the navigation cache code to match standard for 5.16.

Before

Code using deprecated code functions

After

Code using standard cache

Technical Details

This creates a new service cache.HRCore_Info which is the standard way of defining Civi cache groups.