[O] Typographical error in org.texi (org-show-todo-key should be org-show-todo-tree)

[Troy Will]

Hi,

I spotted an obvious typographical error in the Org mode manual. There is
no "org-show-todo-key" function. Change "org-show-todo-key" to
"org-show-tree" on line 3785 of org.texi to fix.

Regards,
Troy