[PROJECT] Load/save export settings to file

[itsmattkc]

Originally opened as https://github.com/sobotka/olive/issues/59

General TODO Summary

Implement serializing the export preferences to/from an XML file.

Additional Information / Notes

Will allow the user to save export presets which could also be used to control the export parameters for headless exporting (#820).

[itsmattkc]

Depends on #1345

[itsmattkc]

Fixed in 5853c114c223877a7eb34e921e057641ba9b8da9