What:		/config/sdcardfs/
Date:		Nov 2017
KernelVersion:	--
Description:	This presents a configfs interface for Android's emulated
		sdcard layer. It relates the names of packages to their
		package ids, so that they can be given access to their app
		specific folders. It also allows you to set information used
		to track data usage for specific sorts of files by their
		extension.

		The attributes:

		remove_userid		- Removes an Android user from all
					package exclude lists
		packages_gid.list	- Displays the first page worth of
					packages, for debugging purposes

What:		/config/sdcardfs/<package>/
Date:		Nov 2017
KernelVersion:	--
Description:	This is where package specific information is set. A package
		is associated with an id, and is accessible only to Android
		users that are not on the excluded_userids list.

		The attributes:

		appid			- The package's id.
		excluded_userids	- Write an Android user id here to
					not have that user see permissions
					that would indicate that app is
					installed.
		clear_userid		- Remove a user from the excluded
					list

What:		/config/sdcardfs/extensions/
Date:		Nov 2017
KernelVersion:	--
Description:	Configure what extensions have tracked storage. This is done
		using the quota feature of the underlying filesystem if
		supported. Create a directory for each group of extensions
		you wish to track together

What:		/config/sdcardfs/extensions/<group>/
Date:		Nov 2017
KernelVersion:	--
Description:	This group represents a set of extensions whose storage usage
		are tracked as a unit. Create a directory for every extension
		you wish to include in the group.

		The attributes:

		ext_gid			- Value to set the gid of files in the
					lower filesystem with the given gid to