Merge pull request #457 from linas/master

Assorted minor postgresql cleanups
Add examples documentation
Rename one of the examples directories
Remove an example; we don't want anyone to do this.

The example is written in a style that no one should be emulating.
I don't want to see anyone copying this, and writing code like this.
Its an "example", not a "sample"

In English, the word "sample" means somthing else...
Add documentation for the agent
make the example agent do something
Add a missing carriage return
Bug fix: the stop-agents command was not working.
expand the agents example
Remove the server example

We do NOT qant to encourage *anyone* to derive from the cogserver class,
This leads to huge headaches when there are multiple classes that have
derived from it; they can no longer be combined, and end up with conflicting
and duplicated functions.  See the embodiment code, as an example of how
bad this can get.
Minor README cleanup.