Update watcardvendors.json

References:
* http://meetpoint.ca/contact.html
* http://www.watcard.uwaterloo.ca/flexoffcampus.html looks like this is no longer a WatCard location.
* http://wikimapia.org/23079596/Meetpoint
* http://www.wolframalpha.com/input/?i=43%C2%B028%2720%22N+++80%C2%B032%279%22W