#3765 [HHQ-3265] Fix handling of removed resource types on plugin

[Hyperic Team]

http://jira.hyperic.com/browse/HHQ-3265


2 issues here,

1) If a plugin developer removes types from a custom HQ plugin, and these types have instances of that type in the HQ inventory the plugin deployment will fail with an error "deleted object would be re-saved by cascade". On redeployment the server attempts to remove unknown types without first removing references to that type from the inventory.

This raises a bigger question:

2) If #1 worked as expected, is that what we want the proper behavior to be? I'm not sure if it's entirely obvious that changing the types in a plugin could result in resources getting deleted from the inventory.