forked from github/szkolny
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* Use MediaStore on SDK level >= 29 for timetable export * Fix imports * Use subdirectory in the Photos folder * Use MediaStore for all API levels * Remove not-null assertion * Remove unnecessary outputStream close. * Use File constructor for directory path * Use File(File, String) constructor Co-authored-by: Kuba Szczodrzyński <kuba@szczodrzynski.pl>