Update Settings handling to be standard practice for 4.7 and onwards …
Created by: seamuslee001
…and clean up some coding style
@nganivet this primarily updates the settings setting and retrieving to be standard as per https://docs.civicrm.org/dev/en/latest/framework/setting/#domain-settings It also just makes some minor code style fixes such as including visibility statements on fuctions. It also bumps up the version number as well