Move transient gridded search to separate class

Hi @dkeitel ,

Currently, I think you are using GridSearch to run your transient grid searches, is that correct? If you continue to develop this, it may make sense to create a specific subclass, say TransientGridSearch. Basically, you do something like

class TransientGridSearch(GridSearch)
    def __init__ ...

This way, TransientGridSearch inherits all methods from GridSearch, but then overwrite any parts it needs to modify.

The benefit is, any other methods which subclass GridSearch, doesn't need to worry about the transient parts (and hence changes to the transient parts won't break anything else).

Is there any reason why this wouldn't work? If not, I'll have a look at creating a patch and seeing what you think