add license/copyright (cc-by-sa).
move more complex pages to examples/ as well.
move sticky header examples as well.
a small index for the examples directory.

it just lists the bigger examples, but that's ok, i think.
more css resources, including bootstrap, webflow & macaw.

macaw is now availlable for windows, which might be really useful for
lots of people...
add grid example.

ugh. i missed that the background-color was on the inner pre elements on
the gridism home page and spent more than an hour looking for the error.

...