manage apps and buckets

[jewlexx]

• Add sfsu export command #481, Added sfsu export command #588
• Add app downloads & various other improvements #491
• feat: add bucket add/rm/list/known commands #741
• Add sfsu bucket outdated and sfsu bucket update commands #571
• sfsu install
• sfsu update
• add uninstall command #786
• sfsu import

[amini8]

sfsu cleanup