Favorite Public Folders

"Favorite" public folders are recorded in the NON_IPM_SUBTREE/Shortcuts directory of the user's mailbox. There is one file for each favorite; the filenames don't matter.

Each favorite has the following properties:

`PR_FAV_DISPLAY_NAME`	`PR_DISPLAY_NAME` of referent
`PR_FAV_DISPLAY_ALIAS`	User-chosen display name. (If not set, use `PR_FAV_DISPLAY_NAME`.)
`PR_FAV_PUBLIC_SOURCE_KEY`	`PR_SOURCE_KEY` of referent
`PR_FAV_PARENT_SOURCE_KEY`	`PR_FAV_PUBLIC_SOURCE_KEY` of parent folder in the Favorites hierarchy
`PR_FAV_LEVEL_MASK`	The depth of the folder in the Favorites hierarchy (first level is `1`)
`PR_FAV_AUTOSUBFOLDERS`	`1` if subfolders should be automatically added as well
`PR_FAV_INHERIT_AUTO`	`1` if all subfolders should be automatically added, as opposed to just immediate subfolders
`PR_FAV_DEL_SUBS`	set if `PR_FAV_AUTOSUBFOLDERS` is set. Uncertain use.

The PR_FAV_PUBLIC_SOURCE_KEY can be used to find the public folder that this favorite points to, by using e2k_entryid_to_permanenturl().