[O] Stuck projects documentation suggestion

[Jon Kristensen]

Hi!

Looking at http://orgmode.org/manual/Stuck-projects.html>, it wasn't 
clear to me that "+PROJECT/-MAYBE-DONE" was something called a "match 
syntax". If the documentation could be extended to include this 
information, and a link to the matching tags and properties page, it 
would be more understandable for new users. (Of course, it would also 
make the page more verbose, but I think the length of this page is short 
enough that it could probably be an acceptable trade-off.)

The docstring for "org-stuck-projects" does include a reference to the 
match syntax. (However, "C-h v" (describe variable) didn't work for 
"org-stuck-projects" for me until I loaded "org-agenda", which was 
surprising from my perspective as a newbie.)

All the best,
Jon