set default property values (as defined in mof) on instances

This is a reminder to set the default property values,
as defined for the class, when creating a new instance.
Currently the default values are not visible.

example:
class Linux_Example : CIM_ManagedElement {
string CreationClassName;
string Name;
uint16 DefaultState = 2;
};

The provider fills only CreationClassName and Name with
values and relies on the CIMOM to set the default value
2 for DefaultState.

current returned instance:
instance of Linux_Example {
CreationClassName = "Linux_Example";
Name = "example_1";
}

the instance that should be returned:
instance of Linux_Example {
CreationClassName = "Linux_Example";
Name = "example_1";
DefaultState = 2;
}