A sys admin could not delete an enterprise that is not their enterprise

Steps to Reproduce
===================
Create a sys admin belonging to abiquo.
Create a new enterprise (XXX por example)
Create an enterprise admin (or sys admin) that belongs to the new enterprise XXX
Log in as XXX ent. admin. Create a VDC and a VAPP. Logout.
Log in as abiquo sys admin.
Try to delete XXX enterprise. A message will appear. You need to delete resources from the enterprise you want to delete.
Try to delete the resources that an enterprise admin for another enterprise has created. There are no visible to you.

Expected Results
=================
A super admin appears.
He is able to delete all they want.

Real Results
============
You need to database and delete by hand all resources or
you need to make a user that belongs to enterprise XXX and delete, then delete enterprise

This is not a correct behavior because you may need a way to delete an enterprise without their agreement. For example, if enterprise violates agreement terms.