Improve the examples

[uvchik]

In the new structure the module header of the examples can be found in the documentation.

Now we may want to improve the module header text and the *title` of some examples. Keep in mind that the title and the first paragraph of the docstring will help users to find a helpfull example.

Check your favourite example and make it more user friendly. If your favourite example is still not part of the upcoming release you can transfer it from the examples repository.

[p-snft]

Examples have been added. I don't see improving them as a blocker for v0.5.0.