fix error in models get_type
fix error in models get_type

Get type uses old style raise which should not be used. The
get_type methods look like they should be returning the value
rather than raising an exception.

	modified:   allocation/models/core.py

CCI-MOC/GUI-Backend,CCI-MOC/GUI-Backend,CCI-MOC/GUI-Backend,CCI-MOC/GUI-Backend