XDG Compliant user package tree -- doc updates.

XDG Compliant user package tree -- doc updates.

This updates the documentation to reflect the new location for user
(early) packages.

	* PROBLEMS: Add section about early-packages locations.

	* README.packages: Update the text relating to user packages.

	* etc/sxemacs.1 (FILES): Ditto.

	* info/lispref/packaging.texi (The User View): Update.

	* info/new-users-guide/custom2.texi (Init File): Typo fix.

	* info/sxemacs-faq.texi (Q5.3.3): Ditto.

	* info/sxemacs/cmdargs.texi (Command Switches): Add
	-user-pkgs-directory.

	* info/sxemacs/startup.texi (Startup Paths): Update for current
	reality.

Signed-off-by: Steve Youngs <steve@sxemacs.org>