Remove "forget=True" from user API

[wesm]

This should be handled as part of tp_dealloc for this object (or, in the interim, set forget = True by default). Or is there a use case for forget=False that I'm missing?

https://github.com/wiseio/paratext/blob/master/python/paratext/core.py#L207

[deads]

The forget parameter should be True in almost all cases to avoid doubling the peak memory. I agree its probably not a detail the user should see.

The only use case for forget=False is low-level testing where you may want to traverse the C++ scratch space more than once.

The problem with tp_dealloc is if you wait until the Python object is destructed to delete the column in C++, the peak memory is much higher than it needs to be.