Re-saving an export removes criteria

[nfourtythree]

I have noticed a little oddity when editing and saving an export. I came across this when adding the ability to add date criteria to exports (which I will submit a pull request for).

It seems any criteria that added to an export are lost if you go in an edit the export and re-save it.

See gif here:

As everyone has said, fantastic plugin and keep up the good work!