[Enhancement] find_by_name() should take object type as parameter

[reubenur-rahman]

Can we introduce object type as parameter for the find_by_name() ?

Suppose I have a DVS name 'test' and a dv port group with same name 'test' in the same DVS. Then I guess the method will be confused.
networkFolder.find_by_name('test') can return either a DVS or a Dv portgroup ! If we provide the object type then I think we are safe.