ni_nitdoc: Generate each class's pages included in a program

Signed-off-by: Stefan Lage <lagestfan@gmail.com>
ni_nitdoc: Adds header/body in class pages

Signed-off-by: Stefan Lage <lagestfan@gmail.com>
ni_nitdoc: Adds function to MProperty

Adding functions to get the local_class of a property, and another to
get the anchor link

Signed-off-by: Stefan Lage <lagestfan@gmail.com>
ni_nitdoc: Adding properties column in class page

Signed-off-by: Stefan Lage <lagestfan@gmail.com>