Only look for folder items matching the given pattern in 'move' and 'list-folder' commands

Add support for 'typename:pattern' syntax in item patterns and use
this internally to make 'move' and 'list-folder' only look for folders
matching the given patterns.
Support creation of folders using 'add folder <name>'

Add missing template for folder items in item_templates.go
Support edits to URLs for existing items in 'edit' command