templatize the envvars file

The envvars file (typically installed into /etc/apache2/envvars) sets some environment variables that are used by the init script.

It sets the user to run as, group, pidfile location, etc.

Previous versions of the cookbook didn't include this file, so the init system would be using the wrong pidfile location, for example, and wouldn't know how to stop/restart apache.

This version uses the same values that are used in the rest of the apache2 configuration.
changing reload command to graceful for rhel family
updating serverspec to play nice with a2_conf changes
reverting earlier commit
Merge branch 'envvars-fix' of https://github.com/caleb/apache2 into caleb-envvars-fix
Merge branch 'caleb-envvars-fix' into COOK-3900
fixing spacing, making restart notification delayed
replaced more static values with attributes
added newline to file