vastly simplified systemd detection, made enable/disable errors clearer
both of which allows us to remove 'service name detection' as if systemd
is init we still use it to handle initscripts.
Fix: Calling svn info to determine if dest is an svn Working Copy, to
support updates in Subfolders with Subversion > 1.8
Fix: Ignoring svn:externals on local Modification Check.
Add: Added Argument switch to alow skipping the svn switch call.