Add convenience methods to NilClass
Add convenience methods to NilClass

Like the methods added to String, these are only added if the user
explicitly requires 'wikitext/nil_class'. They add a "w" and a
"to_wikitext" method to the NilClass.

This in turn enables code which might look like this:

  body = @article.body
  body.nil? ? '' : body.w

To simply be written as:

  @article.body.w

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

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