Scaladoc enhancement 2

Hi Donna,

I just finished the first draft for the small triangles on methods.
Please find a ZIP file with the changes attached. The changes are made
based on my previous work on the class comments.

The changed / new files are: "template.css", "template.js",
"arrow-right.png" and "arrow-down.png".

The HTML is unchanged from my last email.

Regards,
Rüdiger