Refactor: templates to format copyright year

Refactor: templates to format copyright year

Up to now, the copyright year was hardcoded in every project template
and had to be updated regularly.
To avoid manual updates and new versions of lfdocs-conf in Pypi,
it is preferable to use python3 datetime import with the format method
to fill and update the year automatically.

Signed-off-by: Guillaume Lambert <guillaume.lambert@orange.com>
Change-Id: I35a7551a80be470dff5b55e0cabb4944a9bab02c