Bug 1119802 - RFE: Support for resource type name change

Added optional attribute "previousNames" for resourceType to plugin
descriptor. This allows server side to correctly handle when resource type
is just renamed (so it does not understand name change as deleted+new)
Suggested change:  "This attribute lists previous names for the type.  To change a type name without losing existing resources of the given type, the previous name must be added to this attribute's value.  If the previous name is not specified it will appear as a new type.  The old type, and it's associated resources, will be removed.  Several previous names can be specified, separated by |."