After shrinking the global example placeholder size, ones with
additional content within the demo area needed to be tweaked
individually, to prevent the other content from wrapping down or
extending off the side of the container.

This allows a page to have multiple placeholders, since we're no longer
tied to unique IDs.

To improve organization with the increasing number of examples, every
example page is now the index of its own subdirectory, which contains
all the files specific to that example.