Addition to the mission statement

Hi!
I've now edited the wiki, and added half a sentence to the second bullet 
of the mission statement as I promised yesterday. Feel free to edit or 
propose something else if you find something more suitable.

The sentence was " Provide an annotated overview of standard 
vocabularies useful for the field."
is now "Provide an annotated overview of standard vocabularies 
(ontologies) useful for the field, and in case additional vocabularies 
(ontologies) corresponding to practitioner needs are required, create 
such vocabularies (ontologies)."

I've also copied some definitions into the glossary and linked them to 
the mission statement. Feel free to add additional definitions if you 
don't agree with them, but my feeling is that this group is quite close 
to the linked data community, and therefore their definitions should 
probably be suitable.

Cheers,
Eva