Foolproof the NEXT_TOKEN macro
Foolproof the NEXT_TOKEN macro

Previously the NEXT_TOKEN macro was a little too much of a dumb wrapper
for the next_token function. Protect the user from shooting himself in
the foot by ensuring that you always pass in a valid pointer when
invoking next_token.

Signed-off-by: Wincent Colaiuta <c76ac2e9cd86441713c7dfae92c451f3e6d17fdc@wincent.com>

geni/wikitext,geni/wikitext,barnaclebarnes/wikitext,geni/wikitext,barnaclebarnes/wikitext,barnaclebarnes/wikitext,wincent/wikitext,wincent/wikitext