Fixes #5845: Add portable init services handling in the Techniques

Ticket: http://www.rudder-project.org/redmine/issues/5845

To be merged in 3.0
The apache_unbootstarted class was defined by some code that you removed above. You can't use it, therefore. But you shuoldn't have too, the point of the method you're calling is to *ensure* it's set to start on boot, so you can just call it unconditionally!