Makes examples less repetitive, adds some explanation, removes unnecessary steps from some examples.

This demo is useful for getting an orientation with using active-fedora 8.  I got stuck on a few things:

1. I couldn't keep track of which object I was looking at because the pids are so long and the titles were all the same
2. All of the demos create a datastream and add content to it, even when it's not part of the demo. This made it seem like you _had_ to always add a datastream
3. I wanted a slightly stronger hint of what each demo is doing

so I added these changes to remedy those issues (slightly).