Examples not beginning with avrprog_ should be renamed

[kattni]

There are four examples not beginning with avrprog_. They should be renamed to begin with that to fit CircuitPython library standards and clarify which library they are associated with in the examples bundle.

The lines including this file name in the docs/examples.rst file must also be updated to reflect the name change, e.g.:

.. literalinclude:: ../examples/current_file_name.py
    :caption: examples/current_file_name.py
    :linenos:

would be updated to:

.. literalinclude:: ../examples/current_file_name_changed.py
    :caption: examples/current_file_name_changed.py
    :linenos:

[ladyada]

examples are all .py

[ladyada]

er, all .py examples are renamed. other files are for demo