Hi all

Bugfix open 1 link from list; doc more link types

* doc/org.texi (External links): Document the link types file+sys and
file+emacs, slightly narrow used page width.
* lisp/org.el (org-offer-links-in-entry): Make list when assigning a
single link.

"M-1 C-c C-o" or (org-open-at-point 1) or (org-offer-links-in-entry 1)
on a headline followed by two links enters Lisp error.  Both changes
are remainders of the commit release_6.33f-189-g3e0c61d.

Michael