literal name_enable wherever possible, and ${name}_enable
when it's not, to prepare for the demise of set_rcvar().
In cases where I had to hand-edit unusual instances also
modify formatting slightly to be more uniform (and in
some cases, correct). This includes adding some $FreeBSD$
tags, and most importantly moving rcvar= to right after
name= so it's clear that one is derived from the other.
* Allow configuration of _confdir and _logfile
* Put the pid file in /var/run/$name with proper permissions
* Clean up pid file and directory on exit, remove log if empty
Feature safe: yes
