due to a %^!&@^ feature in the latest version of yum we are creating a

due to a %^!&@^ feature in the latest version of yum we are creating a
/vservers directory within a vserver. This throws off the
vbuild-nightly, as it checks whether it is operating within a vserver
by checking for the existence of the /vservers directory.

Changed it to check for /etc/vservers instead, which isn't exactly the
best test either.  It would be better if one could easily check
whether one was running inside the root context or inside a vserver.